import java.util.*;
import java.util.zip.*;
import java.util.List;
import java.util.regex.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.table.*;
import java.io.*;
import java.net.*;
import java.lang.reflect.*;
import java.lang.ref.*;
import java.lang.management.*;
import java.security.*;
import java.security.spec.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.imageio.*;
import java.math.*;
public class main {


public static void main(String[] args) throws Exception {
  Prolog p = new Prolog();
  int n = p.mark();
  p.addStatement(" \"Piko\" schreibt man \"Pico\" ");
  p.addStatement(" \"Pico\" schreibt man \"Pico\" ");
  String x = p.solveAsText(print(" \"Piko\" schreibt man $x "), "x");
  assertEqualsVerbose(quote("Pico"), x);
  print("ok");
}

static volatile StringBuffer local_log = new StringBuffer(); // not redirected
static volatile StringBuffer print_log = local_log; // might be redirected, e.g. to main bot

// in bytes - will cut to half that
static volatile int print_log_max = 1024*1024;
static volatile int local_log_max = 100*1024;

static void print() {
  print("");
}

// slightly overblown signature to return original object...
static <A> A print(A o) {
  String s = String.valueOf(o) + "\n";
  StringBuffer loc = local_log;
  StringBuffer buf = print_log;
  int loc_max = print_log_max;
  if (buf != loc && buf != null) {
    print_append(buf, s, print_log_max);
    loc_max = local_log_max;
  }
  if (loc != null) 
    print_append(loc, s, loc_max);
  System.out.print(s);
  return o;
}

static void print(long l) {
  print(String.valueOf(l));
}

static void print_append(StringBuffer buf, String s, int max) {
  synchronized(buf) {
    buf.append(s);
    max /= 2;
    if (buf.length() > max) try {
      int newLength = max/2;
      int ofs = buf.length()-newLength;
      String newString = buf.substring(ofs);
      buf.setLength(0);
      buf.append("[...] ").append(newString);
    } catch (Exception e) {
      buf.setLength(0);
    }
  }
}
  static String quote(String s) {
    if (s == null) return "null";
    return "\"" + s.replace("\\", "\\\\").replace("\"", "\\\"").replace("\r", "\\r").replace("\n", "\\n") + "\"";
  }
  
  static String quote(long l) {
    return quote("" + l);
  }

static void assertEqualsVerbose(Object x, Object y) {
  assertEqualsVerbose(null, x, y);
}

static void assertEqualsVerbose(String msg, Object x, Object y) {
  if (!(x == null ? y == null : x.equals(y)))
    fail((msg != null ? msg + ": " : "") + structure(x) + " != " + structure(y));
  else
    print("assertEqualsVerbose OK: " + structure(x));
}

  static RuntimeException fail() {
    throw new RuntimeException("fail");
  }
  
  static RuntimeException fail(Object msg) {
    throw new RuntimeException(String.valueOf(msg));
  }
  
  static RuntimeException fail(String msg) {
    throw new RuntimeException(unnull(msg));
  }
    
  static RuntimeException fail(String msg, Object... args) {
    throw new RuntimeException(format(msg, args));
  }
// "seen" is now default
static String structure(Object o) {
  return structure(o, 0, new IdentityHashMap());
}

static String structure_seen(Object o) {
  return structure(o, 0, new IdentityHashMap());
}

// leave to false, unless unstructure() breaks
static boolean structure_allowShortening = false;
  
static String structure(Object o, int stringSizeLimit, IdentityHashMap<Object, Integer> seen) {
  if (o == null) return "null";
  
  // these are never back-referenced (for readability)
  
  if (o instanceof String)
    return quote(stringSizeLimit != 0 ? shorten((String) o, stringSizeLimit) : (String) o);
    
  if (o instanceof BigInteger)
    return "bigint(" + o + ")";
  
  if (o instanceof Double)
    return "d(" + quote(str(o)) + ")";
    
  if (o instanceof Long)
    return o + "L";
  
  if (seen != null) {
    Integer ref = seen.get(o);
    if (ref != null)
      return "r" + ref;
      
    seen.put(o, seen.size()+1);
  }

  String name = o.getClass().getName();

  StringBuilder buf = new StringBuilder();
  
  if (o instanceof HashSet)
    return "hashset" + structure(new ArrayList((Set) o), stringSizeLimit, seen);

  if (o instanceof TreeSet)
    return "treeset" + structure(new ArrayList((Set) o), stringSizeLimit, seen);
  
  if (o instanceof Collection) {
    for (Object x : (Collection) o) {
      if (buf.length() != 0) buf.append(", ");
      buf.append(structure(x, stringSizeLimit, seen));
    }
    return "[" + buf + "]";
  }
  
  if (o instanceof Map) {
    for (Object e : ((Map) o).entrySet()) {
      if (buf.length() != 0) buf.append(", ");
      buf.append(structure(((Map.Entry) e).getKey(), stringSizeLimit, seen));
      buf.append("=");
      buf.append(structure(((Map.Entry) e).getValue(), stringSizeLimit, seen));
    }
    return (o instanceof HashMap ? "hashmap" : "") + "{" + buf + "}";
  }
  
  if (o.getClass().isArray()) {
    int n = Array.getLength(o);
    for (int i = 0; i < n; i++) {
      if (buf.length() != 0) buf.append(", ");
      buf.append(structure(Array.get(o, i), stringSizeLimit, seen));
    }
    return "array{" + buf + "}";
  }

  if (o instanceof Class)
    return "class(" + quote(((Class) o).getName()) + ")";
    
  if (o instanceof Throwable)
    return "exception(" + quote(((Throwable) o).getMessage()) + ")";
    
  // Need more cases? This should cover all library classes...
  if (name.startsWith("java.") || name.startsWith("javax."))
    return String.valueOf(o);
    
  String shortName = o.getClass().getName().replaceAll("^main\\$", "");
  
  if (shortName.equals("Lisp")) {
    buf.append("l(" + structure(getOpt(o, "head"), stringSizeLimit, seen));
    List args = (List) ( getOpt(o, "args"));
    if (nempty(args))
      for (int i = 0; i < l(args); i++) {
        buf.append(", ");
        Object arg = args.get(i);
        
        // sweet shortening
        if (arg != null && eq(arg.getClass().getName(), "main$Lisp") && isTrue(call(arg, "isEmpty")))
          arg = get(arg, "head");
          
        buf.append(structure(arg, stringSizeLimit, seen));
      }
    buf.append(")");
    return str(buf);
  }
    
  int numFields = 0;
  String fieldName = "";
  if (shortName.equals("DynamicObject")) {
    shortName = (String) get(o, "className");
    Map<String, Object> fieldValues = (Map) get(o, "fieldValues");
    
    for (String _fieldName : fieldValues.keySet()) {
      fieldName = _fieldName;
      Object value = fieldValues.get(fieldName);
      if (value != null) {
        if (buf.length() != 0) buf.append(", ");
        buf.append(fieldName + "=" + structure(value, stringSizeLimit, seen));
      }
      ++numFields;
   }
  } else {
    // regular class
    // TODO: go to superclasses too
    Field[] fields = o.getClass().getDeclaredFields();
    for (Field field : fields) {
      if ((field.getModifiers() & Modifier.STATIC) != 0)
        continue;
      fieldName = field.getName();
      
      // skip outer object reference
      if (fieldName.indexOf("$") >= 0) continue;

      Object value;
      try {
        field.setAccessible(true);
        value = field.get(o);
      } catch (Exception e) {
        value = "?";
      }
      
      // put special cases here...
  
      if (value != null) {
        if (buf.length() != 0) buf.append(", ");
        buf.append(fieldName + "=" + structure(value, stringSizeLimit, seen));
      }
      ++numFields;
    }
  }
  
  String b = buf.toString();
  
  if (numFields == 1 && structure_allowShortening)
    b = b.replaceAll("^" + fieldName + "=", ""); // drop field name if only one
  String s = shortName;
  if (buf.length() != 0)
    s += "(" + b + ")";
  return s;
}


  static String unnull(String s) {
    return s == null ? "" : s;
  }
  
  static List unnull(List l) {
    return l == null ? emptyList() : l;
  }
  static String format(String pat, Object... args) {
    return format3(pat, args);
  }

static boolean nempty(Collection c) {
  return !isEmpty(c);
}

static boolean nempty(String s) {
  return !isEmpty(s);
}
static int l(Object[] array) {
  return array == null ? 0 : array.length;
}

static int l(byte[] array) {
  return array == null ? 0 : array.length;
}

static int l(int[] array) {
  return array == null ? 0 : array.length;
}

static int l(char[] array) {
  return array == null ? 0 : array.length;
}

static int l(Collection c) {
  return c == null ? 0 : c.size();
}

static int l(Map m) {
  return m == null ? 0 : m.size();
}

static int l(String s) {
  return s == null ? 0 : s.length();
} 


static boolean eq(Object a, Object b) {
  if (a == null) return b == null;
  if (a.equals(b)) return true;
  if (a instanceof BigInteger) {
    if (b instanceof Integer) return a.equals(BigInteger.valueOf((Integer) b));
    if (b instanceof Long) return a.equals(BigInteger.valueOf((Long) b));
  }
  return false;
}
static String str(Object o) {
  return String.valueOf(o);
}
  // varargs assignment fixer for a single string array argument
  static Object call(Object o, String method, String[] arg) {
    return call(o, method, new Object[] {arg});
  }
  
  static Object call(Object o, String method, Object... args) {
    try {
      if (o instanceof Class) {
        Method m = call_findStaticMethod((Class) o, method, args, false);
        m.setAccessible(true);
        return m.invoke(null, args);
      } else {
        Method m = call_findMethod(o, method, args, false);
        m.setAccessible(true);
        return m.invoke(o, args);
      }
    } catch (Exception e) {
      throw e instanceof RuntimeException ? (RuntimeException) e : new RuntimeException(e);
    }
  }

  static Method call_findStaticMethod(Class c, String method, Object[] args, boolean debug) {
    Class _c = c;
    while (c != null) {
      for (Method m : c.getDeclaredMethods()) {
        if (debug)
          System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
        if (!m.getName().equals(method)) {
          if (debug) System.out.println("Method name mismatch: " + method);
          continue;
        }

        if ((m.getModifiers() & Modifier.STATIC) == 0 || !call_checkArgs(m, args, debug))
          continue;

        return m;
      }
      c = c.getSuperclass();
    }
    throw new RuntimeException("Method '" + method + "' (static) with " + args.length + " parameter(s) not found in " + _c.getName());
  }

  static Method call_findMethod(Object o, String method, Object[] args, boolean debug) {
    Class c = o.getClass();
    while (c != null) {
      for (Method m : c.getDeclaredMethods()) {
        if (debug)
          System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
        if (m.getName().equals(method) && call_checkArgs(m, args, debug))
          return m;
      }
      c = c.getSuperclass();
    }
    throw new RuntimeException("Method '" + method + "' (non-static) with " + args.length + " parameter(s) not found in " + o.getClass().getName());
  }

  private static boolean call_checkArgs(Method m, Object[] args, boolean debug) {
    Class<?>[] types = m.getParameterTypes();
    if (types.length != args.length) {
      if (debug)
        System.out.println("Bad parameter length: " + args.length + " vs " + types.length);
      return false;
    }
    for (int i = 0; i < types.length; i++)
      if (!(args[i] == null || isInstanceX(types[i], args[i]))) {
        if (debug)
          System.out.println("Bad parameter " + i + ": " + args[i] + " vs " + types[i]);
        return false;
      }
    return true;
  }


static boolean isTrue(Object o) {
  return booleanValue(o);
}
static String shorten(String s, int max) {
  if (s == null) return "";
  return s.length() <= max ? s : s.substring(0, Math.min(s.length(), max)) + "...";
}
static Object getOpt(Object o, String field) {
  if (o instanceof String) o = getBot ((String) o);
  if (o == null) return null;
  if (o instanceof Class) return getOpt((Class) o, field);
  
  if (o.getClass().getName().equals("main$DynamicObject"))
    return call(getOpt_raw(o, "fieldValues"), "get", field);
  
  if (o instanceof Map) return ((Map) o).get(field);
  
  return getOpt_raw(o, field);
}

static Object getOpt_raw(Object o, String field) {
  try {
    Field f = getOpt_findField(o.getClass(), field);
    if (f == null) return null;
    f.setAccessible(true);
    return f.get(o);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Object getOpt(Class c, String field) {
  try {
    Field f = getOpt_findStaticField(c, field);
    if (f == null) return null;
    f.setAccessible(true);
    return f.get(null);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Field getOpt_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}

static Field getOpt_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  return null;
}
// get purpose 1: access a list/array (safer version of x.get(y))

static <A> A get(List<A> l, int idx) {
  return idx >= 0 && idx < l(l) ? l.get(idx) : null;
}

static <A> A get(A[] l, int idx) {
  return idx >= 0 && idx < l(l) ? l[idx] : null;
}

// get purpose 2: access a field by reflection or a map

static Object get(Object o, String field) {
  if (o instanceof Class) return get((Class) o, field);
  
  if (o instanceof Map)
    return ((Map) o).get(field);
    
  if (o.getClass().getName().equals("main$DynamicObject"))
    return call(get_raw(o, "fieldValues"), "get", field);
    
  return get_raw(o, field);
}

static Object get_raw(Object o, String field) {
  try {
    Field f = get_findField(o.getClass(), field);
    f.setAccessible(true);
    return f.get(o);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Object get(Class c, String field) {
  try {
    Field f = get_findStaticField(c, field);
    f.setAccessible(true);
    return f.get(null);
  } catch (Exception e) {
    throw new RuntimeException(e);
  }
}

static Field get_findStaticField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & Modifier.STATIC) != 0)
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
}

static Field get_findField(Class<?> c, String field) {
  Class _c = c;
  do {
    for (Field f : _c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    _c = _c.getSuperclass();
  } while (_c != null);
  throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
}

// extended over Class.isInstance() to handle primitive types
static boolean isInstanceX(Class type, Object arg) {
  if (type == boolean.class) return arg instanceof Boolean;
  if (type == int.class) return arg instanceof Integer;
  if (type == long.class) return arg instanceof Long;
  if (type == float.class) return arg instanceof Float;
  if (type == short.class) return arg instanceof Short;
  if (type == char.class) return arg instanceof Character;
  if (type == byte.class) return arg instanceof Byte;
  if (type == double.class) return arg instanceof Double;
  return type.isInstance(arg);
}
  static String format3(String pat, Object... args) {
    if (args.length == 0) return pat;
    
    List<String> tok = javaTokPlusPeriod(pat);
    int argidx = 0;
    for (int i = 1; i < tok.size(); i += 2)
      if (tok.get(i).equals("*"))
        tok.set(i, format3_formatArg(argidx < args.length ? args[argidx++] : "null"));
    return join(tok);
  }
  
  static String format3_formatArg(Object arg) {
    if (arg == null) return "null";
    if (arg instanceof String) {
      String s = (String) arg;
      return isIdentifier(s) || isNonNegativeInteger(s) ? s : quote(s);
    }
    if (arg instanceof Integer || arg instanceof Long) return String.valueOf(arg);
    return quote(structure(arg));
  }
  

static boolean isEmpty(Collection c) {
  return c == null || c.isEmpty();
}

static boolean isEmpty(String s) {
  return s == null || s.length() == 0;
}
static List emptyList() {
  return Collections.emptyList();
}
static Object getBot(String botID) {
  return call(getMainBot(), "getBot", botID);
}

static boolean booleanValue(Object o) {
  return eq(true, o);
}

static boolean isIdentifier(String s) {
  return isJavaIdentifier(s);
}
static Object mainBot;

static Object getMainBot() {
  return mainBot;
}
  public static String join(String glue, Iterable<String> strings) {
    StringBuilder buf = new StringBuilder();
    Iterator<String> i = strings.iterator();
    if (i.hasNext()) {
      buf.append(i.next());
      while (i.hasNext())
        buf.append(glue).append(i.next());
    }
    return buf.toString();
  }
  
  public static String join(String glue, String[] strings) {
    return join(glue, Arrays.asList(strings));
  }
  
  public static String join(Iterable<String> strings) {
    return join("", strings);
  }
  
  public static String join(String[] strings) {
    return join("", strings);
  }

static boolean isNonNegativeInteger(String s) {
  return s != null && Pattern.matches("\\d+", s);
}
// This is made for NL parsing.
// It's javaTok extended with "..." token, "$n" and "#n" and
// special quotes (which are converted to normal ones).

static List<String> javaTokPlusPeriod(String s) {
  List<String> tok = new ArrayList<String>();
  int l = s.length();
  
  int i = 0;
  while (i < l) {
    int j = i;
    char c; String cc;
    
    // scan for whitespace
    while (j < l) {
      c = s.charAt(j);
      cc = s.substring(j, Math.min(j+2, l));
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
        ++j;
      else if (cc.equals("/*")) {
        do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/"));
        j = Math.min(j+2, l);
      } else if (cc.equals("//")) {
        do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0);
      } else
        break;
    }
    
    tok.add(s.substring(i, j));
    i = j;
    if (i >= l) break;
    c = s.charAt(i);
    cc = s.substring(i, Math.min(i+2, l));

    // scan for non-whitespace
    if (c == '\u201C' || c == '\u201D') c = '"'; // normalize quotes
    if (c == '\'' || c == '"') {
      char opener = c;
      ++j;
      while (j < l) {
        char _c = s.charAt(j);
        if (_c == '\u201C' || _c == '\u201D') _c = '"'; // normalize quotes
        if (_c == opener) {
          ++j;
          break;
        } else if (s.charAt(j) == '\\' && j+1 < l)
          j += 2;
        else
          ++j;
      }
      if (j-1 >= i+1) {
        tok.add(opener + s.substring(i+1, j-1) + opener);
        i = j;
        continue;
      }
    } else if (Character.isJavaIdentifierStart(c))
      do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || s.charAt(j) == '\'')); // for things like "this one's"
    else if (Character.isDigit(c))
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
    else if (cc.equals("[[")) {
      do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]"));
      j = Math.min(j+2, l);
    } else if (cc.equals("[=") && i+2 < l && s.charAt(i+2) == '[') {
      do ++j; while (j+2 < l && !s.substring(j, j+3).equals("]=]"));
      j = Math.min(j+3, l);
    } else if (s.substring(j, Math.min(j+3, l)).equals("..."))
      j += 3;
    else if (c == '$' || c == '#')
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
    else
      ++j;

    tok.add(s.substring(i, j));
    i = j;
  }
  
  if ((tok.size() % 2) == 0) tok.add("");
  return tok;
}


static boolean isJavaIdentifier(String s) {
  if (s.length() == 0 || !Character.isJavaIdentifierStart(s.charAt(0)))
    return false;
  for (int i = 1; i < s.length(); i++)
    if (!Character.isJavaIdentifierPart(s.charAt(i)))
      return false;
  return true;
}


static final class Prolog {
  boolean upperCaseVariables = false; // true for SNL, false for NL
  long varCount;
  boolean showStuff;
  List<Entry> stack = new ArrayList<Entry>();
  Trail sofar = null;
  List<Clause> program = new ArrayList<Clause>();
  List<List<Clause>> programByArity = new ArrayList<List<Clause>>();
  long steps;
  List<String> log;
  int maxLogSize = 1000; // lines
  int maxLevel = 10000; // max stack size
  int timeLimit = 20; // 20 seconds
  long startTime;
  boolean allowEval = true;
  
  // name of theory to memorize stuff to
  String outTheory;
  
  // stats
  int maxLevelSeen; // maximum stack level reached during computation
  long topUnifications, exceptions;

  static interface Native {
    public boolean yo(Prolog p, Lisp term);
  }

  boolean headeq(String a, String b) {
    return isQuoted (a) ? eq(a, b) : eqic(a, b);
  }
  
  static class Var extends Lisp {
    long id;
    Lisp instance;
    
    Var(String name) {
      super(name);
      instance = this;
    }
    
    Var(long id) {
      super("___");
      this.id = id;
      instance = this;
    }
    
    void reset() { instance = this; }
    
    public String toString() {
      if (instance != this)
        return instance.toString();
      return prettyName();
    }
    
    String prettyName() {
      return isUserVar() ? getName() : "_" + id;
    }
    
    boolean isUserVar() {
      return id == 0;
    }
    
    String getName() {
      return head;
    }
    
    Lisp getValue() {
      Lisp l = instance;
      while (l instanceof Var) {
        Var v = (Var) ( l);
        if (v.instance == v)
          return v;
        l = v.instance;
      }
      return l;
    }
  }
  
  static class Collector extends Lisp {
    List<Lisp> solutions = new ArrayList<Lisp>();
    
    Collector() { super("___"); }
    
    public String toString() {
      return "<collector>";
    }
  }
  
  static class Clause {
    Lisp head;
    String loadedFrom; // theory name
    boolean used;
    
    // Either body or nat will be set (or none)
    Native nat;
    Goal body;
    
    Clause(Lisp head, Native nat) {
  this.nat = nat;
  this.head = head;}
    Clause(Lisp head, Goal body) {
  this.body = body;
  this.head = head;}
    Clause(Lisp head, Goal body, Native nat) {
  this.nat = nat;
  this.body = body;
  this.head = head;}
    Clause(Lisp head) {
  this.head = head;}
    
    Clause copy(Prolog p) {
      return new Clause(p.copy(head), body == null ? null : body.copy(p), nat);
    }
    
    public String toString() {
      //ret head + " :- " + (body == null ? "true" : body);
      return nat != null ? head + " :- native" :
        (body == null ? head.toString() : head + " :- " + body);
    }
  }
  
  class Trail {
    Var tcar;
    Trail tcdr;
    
    Trail(Var tcar, Trail tcdr) {
  this.tcdr = tcdr;
  this.tcar = tcar;}
  }
  
  Trail Trail_Note() { return sofar; }
  void Trail_Set(Var x, Lisp value) {
    sofar = new Trail(x, sofar);
    x.instance = value;
    /*if (showStuff)
      log(indent(level()) + "  Push " + x.prettyName() + " (" + x + ")");*/
  }
  void Trail_Undo(Trail whereto) {
    for (; sofar != whereto; sofar = sofar.tcdr) {
      /*if (showStuff)
        log(indent(level()) + "  Resetting variable " + sofar.tcar.prettyName() + " (" + sofar.tcar + ")");*/
      sofar.tcar.reset();
    }
  }
  
  static class TermVarMapping {
    List<Var> vars = new ArrayList<Var>();
    
    TermVarMapping(List<Var> vars) {
  this.vars = vars;}
    TermVarMapping(Var... vars) { this.vars.addAll(asList(vars)); }
    
    void showanswer() {
      print("TRUE.");
      for (Var v : vars)
        print("  " + v.prettyName() + " = " + v);
    }
  }
      
  static class Goal {
    Lisp car;
    Goal cdr;
    
    Goal(Lisp car, Goal cdr) {
  this.cdr = cdr;
  this.car = car;}
    Goal(Lisp car) {
  this.car = car;}
    
    public String toString() {
      return cdr == null ? car.toString() : car + "; " + cdr;
    }
    
    Goal copy(Prolog p) {
      return new Goal(p.copy(car),
        cdr == null ? null : cdr.copy(p));
    }
    
    Goal append(Goal l) {
      return new Goal(car, cdr == null ? l : cdr.append(l));
    }
    
  } // class Goal
  
  boolean unifyOrRollback(Lisp a, Lisp b) {
    Trail t = Trail_Note();
    if (unify(a, b)) return true;
    Trail_Undo(t);
    return false;
  }
  
  boolean unify(Lisp thiz, Lisp t) {
    if (thiz == null) fail("thiz=null");
    if (t == null) fail("t=null");
    
    if (thiz instanceof Var) { // TermVar::unify
      Var v = (Var) ( thiz);
      if (v.instance != v)
        return unify(v.instance, t);
      Trail_Set(v, t);
      return true;
    }
    
    // TermCons::unify
    return unify2(t, thiz);
  }
  
  boolean unify2(Lisp thiz, Lisp t) { 
    if (thiz instanceof Var)
      return unify(thiz, t);
   
    int arity = thiz.size();
    if (!headeq(thiz.head, t.head) || arity != t.size())
      return false;
    for (int i = 0; i < arity; i++)
      if (!unify(thiz.get(i), t.get(i)))
        return false;
    return true;
  }
  
  Lisp copy(Lisp thiz) {
    if (thiz instanceof Var) {
      Var v = (Var) ( thiz);
      if (v.instance == v) {
        Trail_Set(v, newVar());
      }
      return v.instance;
    }
    
    // copy2 (copy non-var)
    Lisp l = new Lisp(thiz.head);
    for (Lisp arg : thiz)
      l.add(copy(arg));
    return l;
  }
  
  Var newVar() {
    return new Var(++varCount);
  }
  
  Var newVar(String name) {
    return new Var(name);
  }
  
  Clause clause(Lisp head, Goal body) {
    return prologify(new Clause(head, body));
  }
  
  // primary processor for freshly parsed rules
  
  Clause clause(Lisp rule) {
    List<Lisp> ops = snlSplitOps(rule);
    /*if (showStuff)
      log("clause(Lisp): " + rule + " => " + structure(ops)); */
      
    // expand rule shortcuts (say/memorize/...)
    
    for (int i = 0; i < l(ops)-1; i++)
      if (ops.get(i).is("memorize *"))
        ops.set(i, lisp("and *", lisp("[]", "memorize", ops.get(i))));
    
    if (!empty(ops) && last(ops).is("say *"))
      ops.set(l(ops)-1, lisp("then *", lisp("[]", "say", last(ops).get(0))));
      
    rule = empty(ops) ? rule : snlJoinOps(ops);

    if (allowEval)
      rule = new EvalTransform().evalTransformRule(rule);
      
    ops = snlSplitOps(rule);
    if (!empty(ops) && last(ops).is("then *")) {
      Lisp head = last(ops).get(0);
      Goal goal = null;
      
      // TODO: check the actual words (if/and/...)
      for (int i = l(ops)-2; i >= 0; i--)
        goal = new Goal(ops.get(i).get(0), goal);
        
      return clause(head, goal);
    } else
      return clause(rule, (Lisp) null);
  }
  
  Clause clause(Lisp head, Lisp body) {
    return clause(head, body == null ? null : new Goal(body));
  }
  
  Lisp prologify(Lisp term) {
    return prologify(term, new HashMap());
  }
  
  Clause prologify(Clause c) {
    HashMap vars = new HashMap();
    c = new Clause(
      prologify(c.head, vars),
      prologify(c.body, vars),
      c.nat);
    /*if (showStuff)
      log("Clause made: " + structure_seen(c));*/
    return c;
  }
  
  Goal prologify(Goal goal, Map<String, Var> vars) {
    if (goal == null) return null;
    return new Goal(
      prologify(goal.car, vars),
      prologify(goal.cdr, vars));
  }
  
  // Note: only for un-prologified
  boolean isVar(Lisp term) {
    return upperCaseVariables ? snlIsVar(term) : nlIsVar(term);
  }
  
  // for prologified (e.g. in native clauses)
  boolean isLiveVar(Lisp term) {
    return term instanceof Var;
  }
  
  Lisp prologify(Lisp term, Map<String, Var> vars) {
    if (term == null) return null;
    if (isVar(term)) {
      Var v = vars.get(term.head);
      if (v == null)
        vars.put(term.head, v = newVar(term.head));
      return v;
    } else {
      Lisp l = new Lisp(term.head);
      for (Lisp arg : term)
        l.add(prologify(arg, vars));
      return l;
    }
  }
  
  List<Var> findVars(Goal g) {
    IdentityHashMap<Var, Boolean> map = new IdentityHashMap<Var, Boolean>();
    while (g != null) {
      findVars(g.car, map);
      g = g.cdr;
    }
    return asList(map.keySet());
  }
  
  List<Var> findVars(Lisp term) {
    IdentityHashMap<Var, Boolean> map = new IdentityHashMap<Var, Boolean>();
    findVars(term, map);
    return asList(map.keySet());
  }
  
  void findVars(Lisp term, IdentityHashMap<Var, Boolean> map) {
    if (term instanceof Var)
      map.put((Var) term, Boolean.TRUE);
    else
      for (Lisp arg : term)
        findVars(arg, map);
  }
  
  static Map<String, Var> makeVarMap(List<Var> vars) {
    HashMap<String, Var> map = new HashMap<String, Var>();
    for (Var v : vars)
      map.put(v.getName(), v);
    return map;
  }
  
  List<Clause> emptyProgram = new ArrayList<Clause>();
  
  // Executor stack entry
  class Entry {
    Goal goal;
    List<Clause> program; // full program or filtered by arity
    int programIdx = 0;
    Trail trail;
    boolean trailSet;

    Entry(Goal goal) {
  this.goal = goal;
      Lisp car = resolve1(goal.car);
      if (car instanceof Var) {
        if (showStuff)
          log("Weird: Goal is variable: " + car);
        program = Prolog.this.program;
      } else {
        int arity = car.size();
        if (showStuff)
          log(indent(level()) + "Goal arity " + arity + ": " + render(car));
        program = arity >= l(programByArity) ? emptyProgram : programByArity.get(arity);
      }
    }
  }
  
  void start(String goal) {
    start(nlParse(goal));
  }
  
  void start(Lisp goal) {
    start(new Goal(prologify(goal)));
  }
  
  String render(Lisp term) {
    return nlUnparse(resolve(term));
  }
  
  String render(Goal goal) {
    return goal == null ? "-" : render(goal.car);
  }
  
  String render(Clause c) {
    return c == null ? "-" : render(c.head);
  }
  
  // warning: doesn't prologify the goal
  void start(Goal goal) {
    if (showStuff)
      log("Starting on goal: " + render(goal));
    steps = 0;
    stack = new ArrayList();
    Trail_Undo(null);
    stackAdd(new Entry(goal));
    startTime = now();
  }
  
  void log(String s) {
    if (log != null) {
      if (l(log) == maxLogSize) {
        log.add("[Log overflow]");
        showStuff = false;
      }
      else if (l(log) < maxLogSize)
        log.add(s);
    } else if (showStuff)
      print("prolog: " + s);
  }
    
  int level() {
    return l(stack)-1;
  }
  
  boolean done() {
    boolean result = empty(stack);
    /*if (showStuff && result)
      log("Done with goal!");*/
    return result;
  }

  boolean gnext(Goal g) {  
    Goal gdash = g.cdr;
    if (gdash == null) {
      if (showStuff)
        log("gnext true");
      return true;
    } else {
      stackAdd(new Entry(gdash));
      return false;
    }
  }
  
  void stackPop() {
    Entry e = popLast(stack);
    if (e.trailSet)
      Trail_Undo(e.trail);
  }
  
  void backToCutPoint(int n) {
    if (showStuff)
      log("back to cut point " + n);
    while (l(stack) >= n) {
      if (showStuff)
        log("cut: dropping " + structure(last(stack).goal));
      stackPop();
    }
  }

  boolean step() {
    if (done()) fail("done!"); // safety
    if (now() >= startTime+timeLimit*1000)
      fail("time limit reached: " + timeLimit + " s");
    
    ++steps;
    Entry e = last(stack);
    
    if (e.trailSet) {
      Trail_Undo(e.trail);
      e.trailSet = false;
    }
    
    e.trail = Trail_Note();
    e.trailSet = true;
    
    // cut operator - suceeds first time
    if (e.goal.car.is("!", 1)) {
      if (showStuff)
        log("cut " + e.programIdx + ". " + structure(e.goal));
      if (e.programIdx == -1) {
        ++e.programIdx;
        return gnext(e.goal);
      } else if (e.programIdx == 0) {
        ++e.programIdx;
        // fails 2nd time and cuts
        //e.goal.car.head = "false"; // super-hack :D
        backToCutPoint(parseInt(e.goal.car.get(0).raw()));
        return false;
      } else {
        stackPop();
        return false;
      }
    }

    if (e.programIdx >= l(e.program)) { // program loop ends
      removeLast(stack);
      return false;
    }
      
    // now in program loop - get next clause to try
    
    Clause cc = e.program.get(e.programIdx);
    ++e.programIdx;
    
    // copy the clause; synchronize on it because it may come
    // from a shared Prolog interpreter
    
    Clause c;
    synchronized(cc) {
      c = cc.copy(this);
      Trail_Undo(e.trail);
    }
    
    String text = null;
    if (showStuff)
      //text = "  Goal: " + e.goal + ". Got clause: " + c;
      text = "Got clause: " + render(c);
    ++topUnifications;
    if (unify(e.goal.car, c.head)) {
      cc.used = true; // mark clause used
      if (showStuff) {
        log(indent(level()) + text);
        log(indent(level()) + "  Clause unifies to: " + render(c));
      }
      Goal gdash;
      if (c.nat != null) {
        if (showStuff)
          log(indent(level()) + " Clause is native.");
        if (!c.nat.yo(this, c.head)) {
          if (showStuff)
            log(indent(level()) + "Native clause fails");
          return false;
        }
        gdash = e.goal.cdr;
      } else
        gdash = c.body == null ? e.goal.cdr : resolveCut(c.body).append(e.goal.cdr);
      if (showStuff)
        log(indent(level()) + "  gdash: " + render(gdash));
        
      if (gdash == null) {
        if (showStuff)
          log("SUCCESS!");
        return true;
      } else {
        Entry e2 = new Entry(gdash);
        /*if (showStuff)
          log(indent(level()) + "New goal: " + render(gdash));*/
        stackAdd(e2);
        return false;
      }
    } /*else
      if (showStuff)
        log(indent(level()) + "No match for clause.");*/
        
    return false;
  }
  
  // resolve cut in clause body
  Goal resolveCut(Goal g) {
    if (g.car.is("!", 0))
      return fixCut(g);
    if (g.cdr == null)
      return g;
    return new Goal(g.car, resolveCut(g.cdr));
  }
  
  // note stack length in cut
  Goal fixCut(Goal g) {
    return new Goal(lisp("!", lstr(stack)), g.cdr); // max. one cut per clause
  }
  
  void stackAdd(Entry e) {
    stack.add(e);
    int n = l(stack);
    if (n > maxLevel) fail("Maximum stack level reached: " + n);
    if (n > maxLevelSeen) maxLevelSeen = n;
  }
  
  void addClause(String text) {
    addClause(nlParse(text));
  }
  
  // synonym of addClause
  void addStatement(String text) {
    addClause(text);
  }
  
  void addClause(Lisp c) {
    addClause(clause(c));
  }
  
  void addClause(Lisp c, String name) {
    addClause(clause(c), name);
  }
  
  void addClause(Clause c) {
    addClause(c, null);
  }
  
  void addClause(Clause c, String name) {
    c.loadedFrom = name;
    program.add(c);
    if (c.head instanceof Var) {
      if (showStuff)
        log("WARNING: Clause is variable, will not be executed right now: " + c);
      return;
    }
    int arity = c.head.size();
    growArityList(arity);
    programByArity.get(arity).add(c);
  }
  
  void growArityList(int arity) {
    while (arity >= l(programByArity))
      programByArity.add(new ArrayList());
  }
  
  boolean canSolve(Lisp goal) {
    return canSolve(new Goal(prologify(goal)));
  }
  
  boolean canSolve(String goal) {
    return canSolve(nlParse(goal));
  }
  
  boolean canSolve(Goal goal) {
    start(goal);
    while (!done())
      if (step())
        return true;
    return false;
  }
  
  String solveAsText(String goal, String var) {
    Map<String, Lisp> solution = solve(goal);
    return solution == null ? null : nlUnparse(solution.get(addPrefix("$", var)));
  }
  
  // return variable map or null if unsolved
  Map<String, Lisp> solve(Lisp goal) {
    start(goal);

    return nextSolution();
  }
  
  Map<String, Lisp> solve(String text) {
    return solve(nlParse(text));
  }
  
  Map<String, Lisp> getUserVarMap() {
    Goal g = stack.get(0).goal;
    if (showStuff)
      log("UserVarMap goal: " + g);
    HashMap<String, Lisp> map = new HashMap<String, Lisp>();
    for (Var v : findVars(g))
      if (v.isUserVar()) {
        Lisp term = resolve(v);
        boolean ok = !(term instanceof Var) || (term != v && ((Var) term).isUserVar());
        if (showStuff)
          log("UserVarMap var " + v + " ok: " + ok);
        if (ok)
          map.put(v.getName(), term);
      }
    return map;
  }
  
  Map<String, Lisp> nextSolution() {
    if (showStuff)
      log("nextSolution");
    int n = 0;
    while (!done()) {
      ++n;
      if (step()) {
        if (showStuff)
          log("  solution found in step " + n);
        return getUserVarMap();
      }
    }
    if (showStuff)
      log("\nNo solution");
    return null;
  }
  
  void addTheory(String text, String name) {
    for (Clause c : parseProgram(text))
      addClause(c, name);
  }
    
  void addTheory(String text, Lisp tree) {
    addTheory(text, tree, null);
  }
  
  void addTheory(String text, Lisp tree, String name) {
    for (Clause c : parseProgram(text, tree))
      addClause(c, name);
  }
  
  List<Clause> parseProgram(String text) {
    return parseProgram(text, nlParse(text));
  }
    
  List<Clause> parseProgram(String text, Lisp tree) {
    List<Clause> l = new ArrayList<Clause>();
    if (nlIsMultipleStatements(text))
      for (Lisp part : tree)
        l.add(clause(part));
    else
      l.add(clause(tree));
    return l;
  }
  
  // Resolve top-level only
  Lisp resolve1(Lisp term) {
    if (term instanceof Var)
      return ((Var) term).getValue();
    return term;
  }
  
  // resolve all variables
  Lisp resolve(Lisp term) {
    term = resolve1(term);
      
    // smart recurse
    for (int i = 0; i < term.size(); i++) {
      Lisp l = term.get(i);
      Lisp r = resolve(l);
      if (l != r) {
        Lisp x = new Lisp(term.head);
        for (int j = 0; j < i; j++)
          x.add(term.get(j));
        x.add(r);
        for (i++; i < term.size(); i++)
          x.add(resolve(term.get(i)));
        return x;
      }
    }
    
    return term;
  }
  
  // looks for a bodyless rule in the program that matches the term
   // todo: eqic
  boolean containsStatement(Lisp term) {
    for (Clause c : program)
      if (c.body == null && c.nat == null && eq(c.head, term))
        return true;
    return false;
  }
  
  // closed == contains no variables
  boolean isClosedTerm(Lisp term) {
    if (term instanceof Var)
      return false;
    else
      for (Lisp arg : term)
        if (!isClosedTerm(arg))
          return false;
    return true;
  }
  
  void addNative(BaseNative n) {
    addClause(prologify(new Clause(nlParse(n.pat), n)), "nat");
  }
  
  void addNatives(BaseNative... l) {
    for (BaseNative n : l)
      addNative(n);
  }
    
  void addNatives(List<BaseNative> l) {
    for (BaseNative n : l)
      addNative(n);
  }
  
  List<Lisp> getStackTerms() {
    List<Lisp> l = new ArrayList<Lisp>();
    for (Entry e : stack)
      l.add(e.goal.car);
    return l;
  }
  
  void logOn() {
    log = new ArrayList();
    showStuff = true;
  }

  static abstract class BaseNative implements Native {
    String pat;
    Prolog p;
    Map<String, Lisp> m;
    
    BaseNative(String pat) {
  this.pat = pat;}
    
    abstract boolean yo();
    
    public boolean yo(Prolog p, Lisp term) {
      m = new HashMap();
      this.p = p;
      try {
        // Terms are always resolved for native code!
        return nlMatch(pat, p.resolve(term), m) && yo();
      } catch (Exception e) {
        ++p.exceptions;
        if (p.showStuff)
          p.log("Exception in native class " + getClass().getName() + ": " + getStackTrace(e));
        return false;
      } finally {
        this.p = null;
      }
    }
    
    boolean unify(String var, Lisp term) {
      return set(var, term);
    }
    
    boolean set(String var, Lisp term) {
      Lisp v = m.get(var);
      if (v == null)
        fail("Variable " + var + " not found");
      return p.unify(v, term);
    }

    boolean unifyForeign(IdentityHashMap<Lisp, String> varMap, Map<String, Lisp> solution) {
      if (p.showStuff)
        p.log("unifyForeign with: " + structure(solution));
      for (Lisp v : varMap.keySet()) {
        String name = varMap.get(v);
        Lisp value = solution.get(name);
        if (value == null) continue;
        if (!p.unify(v, escapeVariables(value))) {
          return false; // rollback?
        }
      }
      return true;
    }
    
    // fills varMap
    Lisp exportVars(Lisp tree, IdentityHashMap<Lisp, String> varMap) {
      if (tree instanceof Var) {
        String name = varMap.get(tree);
        if (name == null) {
          name = "$_" + (varMap.size()+1);
          varMap.put(tree, name);
        }
        return lisp(name);
      }
      
      Lisp lisp = new Lisp(tree.head);
      for (Lisp sub : tree)
        lisp.add(exportVars(sub, varMap));
      return lisp;
    }
    
    // var = without $
    Lisp get(String var) {
      return m.get(var);
    }
    
    String unq(String var) {
      return m.get(var).unq();
    }
  } // BaseNative
  
  // Prolog constructor
  Prolog() {
    addClause(lisp("true"));
    addBaseNatives();
  }
  
  static class State {
    Trail trail;
    List<Entry> stack;
  }
  
  State saveState() {
    State s = new State();
    s.trail = sofar;
    s.stack = stack;
    sofar = null;
    return s;
  }
  
  void restoreState(State s) {
    sofar = s.trail;
    stack = s.stack;
  }
  
  // auto-rewrite with all clauses in DB
  List<Lisp> rewrite() {
    return rewriteWith(program);
  }
  
  List<Lisp> rewriteWith(List<Clause> rewriteTheory) {
    List<Lisp> result = new ArrayList<Lisp>();
    
    for (Prolog.Clause clause : rewriteTheory) {
      if (clause.body == null) continue; // need conditions to rewrite anything
      
      // usual safe clause copying
      
      Trail t = Trail_Note();
      Clause c;
      synchronized(clause) {
        c = clause.copy(this);
        Trail_Undo(t);
      }
      
      State state = saveState();
      try {
        start(c.body);
        while (!done()) {
          if (step()) {
            Lisp term = resolve(c.head);
            if (!isClosedTerm(term)) {
              if (showStuff)
                log("Not a closed term, skipping: " + term);
              continue;
            }
            
            if (containsStatement(term)) {
              if (showStuff)
                log("Statement exists, skipping: " + term);
              continue;
            }
            
            if (result.contains(term))
              continue;
              
            if (showStuff)
              log("Found new statement: " + term);
            result.add(term);
          }
        }
      } finally {
        restoreState(state);
      }
    }

    return result;
  }
  
  static class NewCollector extends BaseNative {
    NewCollector() { super("$x = new collector"); }
    
    boolean yo() {
      return set("x", new Collector());
    }
  }
  
  class Save extends BaseNative {
    Save() { super("saveTo($x, $collector)"); }
    
    boolean yo() {
      Collector collector = (Collector) get("collector");
      Lisp x = get("x");
      collector.solutions.add(resolve(x));
      return true;
    }
  }
  
  static class Retrieve extends BaseNative {
    Retrieve() { super("$x = retrieve($collector)"); }
    
    boolean yo() {
      print("Retrieve: collector = " + get("collector"));
      Collector collector = (Collector) get("collector");
      return set("x", nlList(collector.solutions));
    }
  }
  
  void addBaseNatives() {
    addNatives(new NewCollector(), new Save(), new Retrieve());
  }
  
  static Lisp escapeVariables(Lisp tree) {
    if (tree instanceof Var) {
      String name = ((Var) tree).prettyName();
      return lisp("[]", "var", name);
    }
    
    Lisp lisp = new Lisp(tree.head);
    for (Lisp sub : tree)
      lisp.add(escapeVariables(sub));
    return lisp;
  }
  
  boolean addClauseIfNew(Lisp clause, String name) {
    if (containsStatement(clause)) return false;
    addClause(clause, name);
    return true;
  }
  
  List<Clause> getUsedClauses() {
    List<Clause> l = new ArrayList<Clause>();
    for (Clause c : program)
      if (c.used)
        l.add(c);
    return l;
  }
  
  List<String> getUsedTheories() {
    TreeSet<String> theories = new TreeSet<String>();
    for (Clause c : getUsedClauses())
      theories.add(or(c.loadedFrom, "?"));
    return asList(theories);
  }
  
  void think(Lisp x) {
    addClauseIfNew(x, "thought");  // TODO: vars and stuff?
  }
  
  List<Lisp> getMemorizedStatements() {
    List<Lisp> l = new ArrayList<Lisp>();
    for (Clause c : program)
      if (c.body == null && c.nat == null && c.head.is("[]", 2) && c.head.get(0).is("memorized"))
        l.add(c.head);
    return l;
  }
  
  String showClause(Clause c) {
    return nlUnparse(c.head) + (c.body == null ? "" : " :- ...");
  }
  
  String showProgram() {
    List<String> l = new ArrayList<String>();
    for (Clause c : program)
      l.add(showClause(c));
    return n(l(program), "statement") + " " + slackSnippet(joinLines(l  ));
  }
  
  void copyProgramFrom(Prolog p) {
    program.addAll(p.program);
    growArityList(l(p.programByArity));
    for (int i = 0; i < l(p.programByArity); i++)
      programByArity.get(i).addAll(p.programByArity.get(i));
  }
  
  void addProgram(List<Clause> clauses, String loadedFrom) {
    for (Clause c : clauses)
      addClause(c, loadedFrom);
  }
  
  void addClauses(String text) {
    addTheory(text, "ad hoc");
  }
  
  List<String> statementsAsText() {
    return statementsAsText(0);
  }
  
  List<String> statementsAsText(int startingFromIndex) {
    List<String> l = new ArrayList<String>();
    for (int i = startingFromIndex; i < l(program); i++) {
      Clause c = program.get(i);
      if (c.nat == null) {
        if (c.body != null)
          l.add("[if ? then " + nlUnparse(c.head, false) + "]"); // TODO
        else
          l.add(nlUnparse(c.head, false));
      }
    }
    return l;
  }
  
  int mark() {
    return l(program);
  }
} // class Prolog


// class for linking Java methods to NL
static class Native {
  Lisp snl;
  SNLMatches m;
  SNLMatches trans;
  boolean printExceptions;
  int exceptions;
  List<String> ins, strings;
  
  Native() {} // good to have
  
  Native(Lisp snl) {
  this.snl = snl;}
  
  // assume it's a Lisp structure from another bot -
  // restructure to import it
  /* *(O o) {
    snl = (Lisp) restructure(o);
  }*/
    
  Native(String s) { snl = snlToTree(s); }
  
  boolean match(String pat) {
    m = new SNLMatches();
    trans = new SNLMatches();
    Lisp tree = snlToTree_cached(pat);
    ins = new ArrayList();
    strings = new ArrayList();
    tree = findInVariables(tree, ins, strings);
    //print("tree now: " + tree);
    if (!snlMatch2(tree, snl, trans))
      return false;
    for (String in : ins)
      if (get(in) == null)
        return false;
    for (String string : strings)
      if (get(string) == null || !get(string).isEmpty())
        return false;
    return true;
  }
  
  Lisp findInVariables(Lisp tree, List<String> ins, List<String> strings) {
    if (tree == null) return tree;

    if (tree.isEmpty()) {
      if (tree.head.startsWith("in S ")) {
        String var = dropPrefix("in S ", tree.head);
        if (startsWithUpperCase(var)) {
          if (!strings.contains(var))
            strings.add(var);
          return lisp(var);
        }
      }
      
      if (tree.head.startsWith("in ")) {
        String var = dropPrefix("in ", tree.head);
        if (startsWithUpperCase(var)) {
          if (!ins.contains(var))
            ins.add(var);
          return lisp(var);
        }
      }
      
      return tree;
    } else {
      // recurse
      Lisp lisp = new Lisp(tree.head);
      for (Lisp child : tree)
        lisp.add(findInVariables(child, ins, strings));
      return lisp;
    }
  }
  
  Lisp get(String var) {
    Lisp val = trans.get(var);
    if (!isVar(val)) return val;
    return getOuter(val.raw());
  }
  
  // if only one in var
  Lisp get() {
    return get(anyInVar());
  }

  // ditto  
  String str() {
    return str(anyInVar());
  }
  
  String anyInVar() {
    if (!empty(ins)) return first(ins);
    return first(strings);
  }
  
  boolean isVar(Lisp l) {
    return l != null && l.isEmpty() && startsWithUpperCase(l.raw());
  }
  
  // called from outside native
  Lisp getOuter(String var) {
    return m.get(var);
  }
  
  // called from inside native
  String str(String var) {
    Lisp val = get(var);
    if (val == null) fail("variable * not set", var);
    if (!val.isEmpty()) fail("variable * not a string: *", var, val);
    return unquote(val.raw());
  }
  
  String strOuter(String var) {
    Lisp val = getOuter(var);
    if (val == null) fail("variable * not set", var);
    if (!val.isEmpty()) fail("variable * not a string: *", var, val);
    return unquote(val.raw());
  }
  
  // may throw an exception if variable problem (already set to different value)
  void set(String var, Object val) {
    if (val instanceof List) val = structure(val); // TODO
    Lisp lisp = val instanceof Lisp ? (Lisp) val : lisp(quote(main.str(val)));
    Lisp outer = trans.get(var);
    if (isVar(outer)) {
      if (!m.put(trans.raw(var), lisp))
        fail();
    } else
      if (!eq(lisp, outer)) {
        //print("neq " + lisp + " != " + outer);
        fail();
      }
  }
  
  boolean callExternal(Object bot) {
    try {
      Object copy = newObject(main.getClass(bot, "main$Native"), quickExport(snl, bot));
      //O copy = quickExport(this, bot);
      if (!isTrue(callOpt(bot, "yo", copy)))
        return false;
        
      m = (SNLMatches) quickImport(main.get(copy, "m"));
      return true;
    } catch (Exception e) {
      handle(e);
      return false;
    }
  }
  
  boolean callExternal(Method yo) {
    try {
      Class c = yo.getDeclaringClass();
      //print("Declaring class: " + c + " (" + identityHashCode(c) + ")");
      Object copy = newObject(main.getClass(c, "main$Native"), quickExport(snl, c));
      if (!isTrue(yo.invoke(null, copy)))
        return false;
        
      m = (SNLMatches) quickImport(main.get(copy, "m"));
      return true;
    } catch (Exception e) {
      handle(e);
      return false;
    }
  }
  
  void handle(Throwable t) {
    if (printExceptions)
      printStackTrace(t);
    ++exceptions;
  }
}


// a map of assignments that can be rolled back to some state
static class SNLMatches {
  HashMap<String, Lisp> map = new HashMap<String, Lisp>();
  List<String> log = new ArrayList<String>();
  
  boolean put(String key, Lisp val) {
    if (map.containsKey(key))
      // existing
      return eq(map.get(key), val);
    
    // new
    map.put(key, val);
    log.add(key);
    return true;
  }
  
  Lisp get(String key) {
    return map.get(key);
  }
  
  String raw(String key) {
    Lisp x = get(key);
    if (x == null) fail("var not set: " + key);
    return x.raw();
  }
  
  boolean containsKey(String key) {
    return map.containsKey(key);
  }
  
  int save() {
    return l(log);
  }
  
  void restore(int i) {
    while (l(log) > i) {
      String key = log.get(l(log)-1);
      map.remove(key);
      log.remove(l(log)-1);
    }
  }
  
  boolean addAll(SNLMatches m) {
    for (String var : m.keySet())
      if (!put(var, m.get(var)))
        return false;
    return true;
  }
  
  Set<String> keySet() {
    return map.keySet();
  }
}

// a Lisp-like form
static class Lisp implements Iterable<Lisp> {
  String head;
  List<Lisp> args = new ArrayList<Lisp>();
  
  Object more; // additional info, user-defined
  
  Lisp() {}
  Lisp(String head) {
  this.head = head;}
  Lisp(String head, Lisp... args) {
  this.head = head;
    this.args.addAll(asList(args));
  }
  Lisp(String head, List args) {
  this.head = head;
    for (Object arg : args) add(arg);
  }
  
  // INEFFICIENT
  public String toString() {
    if (args.isEmpty())
      return quoteIfNotIdentifier(head);
    List<String> bla = new ArrayList<String>();
    for (Lisp a : args)
      bla.add(a.toString());
    String inner = join(", ", bla);
    if (head.equals(""))
      return "{" + inner + "}"; // list
    else
      return quoteIfNotIdentifier(head) + "(" + inner + ")";
  }

  String raw() {
    if (!isEmpty ()) fail("not raw: " + this);
    return head;
  }
  
  Lisp add(Lisp l) {
    args.add(l);
    return this;
  }
  
  Lisp add(String s) {
    args.add(new Lisp(s));
    return this;
  }
  
  Lisp add(Object o) {
    if (o instanceof Lisp) add((Lisp) o);
    else if (o instanceof String) add((String) o);
    else fail("Bad argument type: " + structure(o));
    return this;
  }
  
  int size() {
    return args.size();
  }
  
  boolean isEmpty() {
    return args.isEmpty();
  }
  
  boolean isLeaf() {
    return args.isEmpty();
  }
  
  Lisp get(int i) {
    return args.get(i);
  }
  
  String getString(int i) {
    return get(i).head;
  }
  
  String s(int i) {
    return getString(i);
  }
  
  boolean isA(String head) {
    return eq(head, this.head);
  }

  boolean is(String head, int size) {
    return isA(head) && size() == size;
  }
  
  boolean is(String head) {
    return isA(head);
  }
  
  boolean is(String... heads) {
    return asList(heads).contains(head);
  }
  
  // check head for one of these (ignore case)
  boolean isic(String... heads) {
    return containsIgnoreCase(heads, head);
  }
  
  public Iterator<Lisp> iterator() {
    return args.iterator();
  }
  
  Lisp subList(int fromIndex, int toIndex) {
    Lisp l = new Lisp(head);
    l.args.addAll(args.subList(fromIndex, toIndex)); // better to copy here I guess - safe
    return l;
  }

  public boolean equals(Object o) {
    if (o == null || o.getClass() != Lisp.class) return false;
    Lisp l = (Lisp) ( o);
    return eq (head, l.head) && eq(args, l.args);
  }
  
  Lisp addAll(List args) {
    for (Object arg : args) add(arg);
    return this;
  }
  
  String unquoted() {
    return unquote(raw());
  }
  
  String unq() {
    return unquoted();
  }
}


  public static String unquote(String s) {
    if (s.startsWith("[")) {
      int i = 1;
      while (i < s.length() && s.charAt(i) == '=') ++i;
      if (i < s.length() && s.charAt(i) == '[') {
        String m = s.substring(1, i);
        if (s.endsWith("]" + m + "]"))
          return s.substring(i+1, s.length()-i-1);
      }
    }
    
    if (s.startsWith("\"") /*&& s.endsWith("\"")*/ && s.length() > 1) {
      String st = s.substring(1, s.endsWith("\"") ? s.length()-1 : s.length());
      StringBuilder sb = new StringBuilder(st.length());
  
      for (int i = 0; i < st.length(); i++) {
        char ch = st.charAt(i);
        if (ch == '\\') {
          char nextChar = (i == st.length() - 1) ? '\\' : st
                  .charAt(i + 1);
          // Octal escape?
          if (nextChar >= '0' && nextChar <= '7') {
              String code = "" + nextChar;
              i++;
              if ((i < st.length() - 1) && st.charAt(i + 1) >= '0'
                      && st.charAt(i + 1) <= '7') {
                  code += st.charAt(i + 1);
                  i++;
                  if ((i < st.length() - 1) && st.charAt(i + 1) >= '0'
                          && st.charAt(i + 1) <= '7') {
                      code += st.charAt(i + 1);
                      i++;
                  }
              }
              sb.append((char) Integer.parseInt(code, 8));
              continue;
          }
          switch (nextChar) {
          case '\\':
              ch = '\\';
              break;
          case 'b':
              ch = '\b';
              break;
          case 'f':
              ch = '\f';
              break;
          case 'n':
              ch = '\n';
              break;
          case 'r':
              ch = '\r';
              break;
          case 't':
              ch = '\t';
              break;
          case '\"':
              ch = '\"';
              break;
          case '\'':
              ch = '\'';
              break;
          // Hex Unicode: u????
          case 'u':
              if (i >= st.length() - 5) {
                  ch = 'u';
                  break;
              }
              int code = Integer.parseInt(
                      "" + st.charAt(i + 2) + st.charAt(i + 3)
                              + st.charAt(i + 4) + st.charAt(i + 5), 16);
              sb.append(Character.toChars(code));
              i += 5;
              continue;
          default:
            ch = nextChar; // added by Stefan
          }
          i++;
        }
        sb.append(ch);
      }
      return sb.toString();      
    } else
      return s; // return original
  }

static Class<?> getClass(String name) {
  try {
    return Class.forName(name);
  } catch (ClassNotFoundException e) {
    return null;
  }
}

static Class getClass(Object o) {
  return o instanceof Class ? (Class) o : o.getClass();
}

static Class getClass(Object realm, String name) { try {
 
  return getClass(realm).getClassLoader().loadClass(name);

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static boolean nlMatch(String pat, String nl, Map<String, Lisp> matches) {
  matches.clear();
  return nlMatch_sub(nlParse/*_cached*/(pat), nlParse(nl), matches);
}

static boolean nlMatch(Lisp pat, String nl, Map<String, Lisp> matches) {
  matches.clear();
  return nlMatch_sub(pat, nlParse(nl), matches);
}

static boolean nlMatch(String pat, Lisp nl, Map<String, Lisp> matches) {
  matches.clear();
  return nlMatch_sub(nlParse/*_cached*/(pat), nl, matches);
}

static boolean nlMatch(Lisp pat, Lisp nl, Map<String, Lisp> matches) {
  matches.clear();
  return nlMatch_sub(pat, nl, matches);
}

static boolean nlMatch_sub(Lisp pat, Lisp nl, Map<String, Lisp> m) {
  if (pat == null || nl == null) return false;
  if (pat.isA("*"))
    return true;
  if (nlIsVar(pat))
    return nlMatch_putMatch(m, pat.head, nl);
    
  if (neq(pat.head, nl.head)) return false;
  
  // heads identical, proceed to children
  int n = pat.size();
  if (n != nl.size()) return false;
  
  for (int i = 0; i < n; i++)
    if (!nlMatch_sub(pat.get(i), nl.get(i), m))
      return false;
      
  return true;
}

static boolean nlMatch_putMatch(Map<String, Lisp> matches, String key, Lisp val) {
  key = dropPrefix("$", key);
  if (matches.containsKey(key) && neq(matches.get(key), val))
    fail("multi-matching not implemented");
  matches.put(key, val);
  return true;
}
  public static String joinLines(List<String> lines) {
    return fromLines(lines);
  }
static boolean nlIsVar(Lisp l) {
  if (l == null || !l.isLeaf()) return false;
  String h = l.head;
  return l(h) > 1 && h.startsWith("$");
}
static <A> ArrayList<A> asList(A[] a) {
  return new ArrayList<A>(Arrays.asList(a));
}

static ArrayList<Integer> asList(int[] a) {
  ArrayList<Integer> l = new ArrayList();
  for (int i : a) l.add(i);
  return l;
}

static <A> ArrayList<A> asList(Set<A> s) {
  return s == null ? new ArrayList() : new ArrayList(s);
}
static boolean empty(Collection c) {
  return isEmpty(c);
}

static boolean empty(String s) {
  return isEmpty(s);
}

static boolean empty(Map map) {
  return map == null || map.isEmpty();
}
static String getStackTrace(Throwable throwable) {
  StringWriter writer = new StringWriter();
  throwable.printStackTrace(new PrintWriter(writer));
  return writer.toString();
}
// supports the usual quotings (', ", variable length double brackets)
static boolean isQuoted(String s) {
  if (s.startsWith("'") || s.startsWith("\"")) return true;
  if (!s.startsWith("[")) return false;
  int i = 1;
  while (i < s.length() && s.charAt(i) == '=') ++i;
  return i < s.length() && s.charAt(i) == '[';
  //return Pattern.compile("^\\[=*\\[").matcher(s).find();
}
static String dropPrefix(String prefix, String s) {
  return s.startsWith(prefix) ? s.substring(l(prefix)) : s;
}
// doesn't perform any sanity checks...
// and this is NL-level, not SNL.
static Lisp snlJoinOps(List<Lisp> ops) {
  Lisp t = lisp("[]");
  for (Lisp op : ops) {
    int i = op.head.indexOf(' ');
    t.add(lisp(substring(op.head, 0, i)));
    t.add(op.get(0));
  }
  return t;
}
static boolean nlIsMultipleStatements(String text) {
  List<String> tok = codeTokens(snlTok(text));
  //ret eq(first(tok), "[") && eq(last(tok), "]");
  
  if (!(eq(first(tok), "[") && eq(last(tok), "]")))
    return false;
    
  List<String> warnings1 = new ArrayList<String>();
  List<String> warnings2 = new ArrayList<String>();
  Lisp parse1 = nlParse(tok, true, warnings1);
  Lisp parse2 = nlParse(subList(tok, 1, l(tok)-1), true, warnings2);
  //ret !eq(parse1, parse2);
  return l(warnings2) > l(warnings1);
  
  //ret isJuxta(tree) && snlSplitOps(tree) == null;
}
static <A> A last(List<A> l) {
  return l.isEmpty() ? null : l.get(l.size()-1);
}
static void printStackTrace(Throwable e) {
  // we go to system.out now - system.err is nonsense
  print(getStackTrace(e));
}

static void printStackTrace() {
  printStackTrace(new Throwable());
}
// make a lisp form
static Lisp lisp(String head, Object... args) {
  Lisp l = new Lisp(head);
  for (Object o : args)
    l.add(o);
  return l;
}

static Lisp lisp(String head, List args) {
  return new Lisp(head, args);
}

static HashMap<String, Lisp>snlToTree_cached_cache = new HashMap();

static Lisp snlToTree_cached(String s) {
  Lisp l = snlToTree_cached_cache.get(s);
  if (l == null)
    snlToTree_cached_cache.put(s, l = snlToTree (s));
  return l;
}
static boolean snlToTree_debug = false;

static Lisp snlToTree(String snl) {
  return snlToTree(snlParse(snl));
}

static Lisp snlToTree(Explain e) {
  class T {
    List<Explain> scanJuxta(Explain e) {
      boolean isJuxta = isA(e, "juxta");
      if (snlToTree_debug)
        print("scanJuxta " + e.string() + " " + isJuxta);
      if (isJuxta) {
        Explain juxta = descend(e, "juxta");
        Explain a = juxta.sub(0), b = juxta.sub(1);
        return concatLists(scanJuxta(a), scanJuxta(b));
      } else
        return litlist(e);
    }
    
    boolean isSame(Explain a, Explain b) {
      return a.fromToken() == b.fromToken() && a.toToken() == b.toToken();
    }
    
    List<String> getClasses(Explain e) {
      List<String> l = new ArrayList<String>();
      while (e != null) {
        l.add(e.className());
        if (l(e.subs) == 1 && e.sub(0) != null && isSame(e, e.sub(0)))
          e = e.sub(0);
        else
          break;
      }
      return l;
    }
    
    Explain castTo(Explain e, String className) {
      return descend(e, className);
    }
    
    Explain descend(Explain e, String className) {
      List<String> l = new ArrayList<String>();
      while (e != null) {
        if (eq(e.className(), className))
          return e;
        if (l(e.subs) == 1)
          e = e.sub(0);
        else
          break;
      }
      return null;
    }
    
    boolean isA(Explain e, String className) {
      return getClasses(e).contains(className);
    }
    
    boolean allAre(List<Explain> l, String className) {
      for (Explain e: l)
        if (!isA(e, className))
          return false;
      return true;
    }
    
    boolean anyAre(List<Explain> l, String className) {
      for (Explain e : l)
        if (isA(e, className))
          return true;
      return false;
    }
    
    List<String> getOperators(List<Explain> parts) {
      List<String> l = new ArrayList<String>();
      for (Explain e : parts)
        l.add(makeOperator(e));
      return l;
    }
    
    // true = it's a sub part
    boolean[] opMap(List<Explain> parts) {
      boolean[] map = new boolean[l(parts)];
      if (anyAre(parts, "symbol")) {
        for (int i = 0; i < l(parts); i++)
          if (!isA(parts.get(i), "symbol"))
            map[i] = true;
      } else
        for (int i = 0; i < l(parts); i++)
          //if (!isA(parts.get(i), "extidentifier"))
          if (!startsWithLetter(parts.get(i).string()))
            map[i] = true;
      return map;
    }
    
    String makeOperatorFromJuxta(List<Explain> parts) {
      List<String> l = new ArrayList<String>();
      boolean[] map = opMap(parts);
      for (int i = 0; i < l(parts); i++) {
        //print("Operator part " + (++i) + ": " + e.string() + " / " + structure(getClasses(e)));
        
        if (map[i])
          l.add("*");
        else
          l.add(parts.get(i).string());
      }
      String op = join(" ", l);
      if (snlToTree_debug)
        print("makeOperatorFromJuxta " + structure(parts) + " => " + op);
      return op;
    }
    
    List<Explain> getJuxtaArgs(List<Explain> parts) {
      List<Explain> l = new ArrayList<Explain>();
      boolean[] map = opMap(parts);
      for (int i = 0; i < l(parts); i++)
        if (map[i])
          l.add(parts.get(i));
      return l;
    }
    
    String makeOperator(Explain e) {
      if (isA(e, "realarrow"))
        return descend(e, "realarrow").sub(0).string() + " *";
      else if (isA(e, "juxta")) {
        List<Explain> j = scanJuxta(e);
        //print("scanJuxta => " + structure(j));
        return makeOperatorFromJuxta(j);
      } else
        return e.string();
    }
    
    Lisp getTree(Explain e) {
      //print("getTree " + structure(getClasses(e)));
      
      if (isA(e, "realarrow")) {
        //print("realarrow");
        Explain a = castTo(e, "realarrow");
        return snlToTree_lisp(e, "<", getTree(a.sub(0)), getTree(a.sub(1)));
      }
      
      if (isA(e, "realarrowr")) {
        //print("realarrowr");
        Explain a = castTo(e, "realarrowr");
        return snlToTree_lisp(e, ">", getTree(a.sub(0)), getTree(a.sub(1)));
      }
      
      if (isA(e, "square")) {
        //print("square");
        Explain a = castTo(e, "square");
        return snlToTree_lisp(e, "[]", getTree(a.sub(0)));
      }
      
      if (isA(e, "round")) {
        Explain a = castTo(e, "round");
        return snlToTree_lisp(e, "()", getTree(a.sub(0)));
      }
      
      if (isA(e, "juxta")) {
        Explain juxta = descend(e, "juxta");
        List<Explain> parts = scanJuxta(juxta);
        
        if (snlToTree_debug) {
          print("juxta " + e.string());
          for (int i = 0; i < l(parts); i++)
            print("  part " + parts.get(i).string() + " " + structure(getClasses(parts.get(i))));
        }
        
        if (l(parts) == 2 && eq(parts.get(0).string(), "="))
          return snlToTree_lisp(e, "= *", removeBrackets(getTree(parts.get(1))));
        else /*if (anyAre(parts, "subword") || anyAre(parts, "ucid")) */ {
          if (snlToTree_debug)
            print("subwords!");
            
          List<Explain> args = getJuxtaArgs(parts);
          Lisp l = snlToTree_lisp(e, makeOperatorFromJuxta(parts));
          for (Explain arg : args)
            l.add(removeBrackets(getTree(arg)));
          return l; // snlSimplifyJuxta(l);
        }
    
        // fall back to simple string
      }
      
      return snlToTree_lisp(e, e.string());
    }

    Lisp removeBrackets(Lisp l) {
      while (l != null && eq(l.head, "[]") && l.size() == 1)
        l = l.get(0);
      return l;
    }
  }
  
  if (e == null) return null;
  return simplifySNLTree(new T().getTree(e));
}

static Lisp snlToTree_lisp(Explain e, String head, Lisp... args) {
  Lisp l = lisp(head, args);
  
  // this is problematic with serialization...
  //SNLInfo info = new SNLInfo();
  //info.originalExplain = e;
  //l.more = info;
  
  return l;
}
static boolean snlIsVar(Lisp l) {
  if (l == null || !l.isLeaf()) return false;
  String h = l.head;
  return startsWithUpperCase(h)
    || (l(h) > 1 && h.startsWith("$"));
}
static Lisp nlList(List list) {
  Lisp tree = lisp("[]");
  for (Object s : list) {
    if (!tree.isEmpty()) tree.add(",");
    if (s instanceof Lisp)
      tree.add((Lisp) s);
    else if (s instanceof String)
      tree.add(quote((String) s));
    else
      tree.add("?");
  }
  return tree;
}
static String indent(int indent) {
  return repeat(' ', indent);
}

static String indent(int indent, String s) {
  return indent(repeat(' ', indent), s);
}

static String indent(String indent, String s) {
  return indent + s.replace("\n", "\n" + indent);
}

static List<String> indent(String indent, List<String> lines) {
  List<String> l = new ArrayList<String>();
  for (String s : lines)
    l.add(indent + s);
  return l;
}
  static Object callOpt(Object o, String method, Object... args) {
    try {
      if (o == null) return null;
      if (o instanceof Class) {
        Method m = callOpt_findStaticMethod((Class) o, method, args, false);
        if (m == null) return null;
        m.setAccessible(true);
        return m.invoke(null, args);
      } else {
        Method m = callOpt_findMethod(o, method, args, false);
        if (m == null) return null;
        m.setAccessible(true);
        return m.invoke(o, args);
      }
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }

  static Method callOpt_findStaticMethod(Class c, String method, Object[] args, boolean debug) {
    Class _c = c;
    while (c != null) {
      for (Method m : c.getDeclaredMethods()) {
        if (debug)
          System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
        if (!m.getName().equals(method)) {
          if (debug) System.out.println("Method name mismatch: " + method);
          continue;
        }

        if ((m.getModifiers() & Modifier.STATIC) == 0 || !callOpt_checkArgs(m, args, debug))
          continue;

        return m;
      }
      c = c.getSuperclass();
    }
    return null;
  }

  static Method callOpt_findMethod(Object o, String method, Object[] args, boolean debug) {
    Class c = o.getClass();
    while (c != null) {
      for (Method m : c.getDeclaredMethods()) {
        if (debug)
          System.out.println("Checking method " + m.getName() + " with " + m.getParameterTypes().length + " parameters");;
        if (m.getName().equals(method) && callOpt_checkArgs(m, args, debug))
          return m;
      }
      c = c.getSuperclass();
    }
    return null;
  }

  private static boolean callOpt_checkArgs(Method m, Object[] args, boolean debug) {
    Class<?>[] types = m.getParameterTypes();
    if (types.length != args.length) {
      if (debug)
        System.out.println("Bad parameter length: " + args.length + " vs " + types.length);
      return false;
    }
    for (int i = 0; i < types.length; i++)
      if (!(args[i] == null || isInstanceX(types[i], args[i]))) {
        if (debug)
          System.out.println("Bad parameter " + i + ": " + args[i] + " vs " + types[i]);
        return false;
      }
    return true;
  }


// snlMatch2 keeps existing matches and restores matches on false

static boolean snlMatch2(String pat, String snl, SNLMatches matches) {
  return snlMatch2(snlToTree_cached(pat), snlToTree(snl), matches);
}

static boolean snlMatch2(Lisp pat, String snl, SNLMatches matches) {
  return snlMatch2(pat, snlToTree(snl), matches);
}

static boolean snlMatch2(String pat, Lisp snl, SNLMatches matches) {
  return snlMatch2(snlToTree_cached(pat), snl, matches);
}

static boolean snlMatch2(Lisp pat, Lisp snl, SNLMatches matches) {
  int level = matches.save();
  if (snlMatch2_sub(pat, snl, matches))
    return true;
  matches.restore(level);
  return false;
}

static boolean snlMatch2_sub(Lisp pat, Lisp snl, SNLMatches m) {
  if (pat == null || snl == null) return false;
  if (pat.isA("*"))
    return true;
  if (startsWithUpperCase(pat.head))
    return snlMatch2_putMatch(m, pat.head, snl);
    
  if (neq(pat.head, snl.head)) return false;
  
  // heads identical, proceed to children
  int n = pat.size();
  if (n != snl.size()) return false;
  
  for (int i = 0; i < n; i++)
    if (!snlMatch2_sub(pat.get(i), snl.get(i), m))
      return false;
      
  return true;
}

static boolean snlMatch2_putMatch(SNLMatches matches, String key, Lisp val) {
  return matches.put(key, val);
}
static void removeLast(List l) {
  if (!l.isEmpty())
    l.remove(l(l)-1);
}
static String quoteIfNotIdentifier(String s) {
  if (s == null) return null;
  return isJavaIdentifier(s) ? s : quote(s);
}
static Object newObject(Class c, Object... args) {
  return nuObject(c, args);
}

static Object newObject(String className, Object... args) {
  return nuObject(className, args);
}

static long now_virtualTime;
static long now() {
  return now_virtualTime != 0 ? now_virtualTime : System.currentTimeMillis();
}

static Object quickImport(Object o) {
  return quickExport(o, mc());
}
static AtomicInteger nlParse_count = new AtomicInteger(); // how often did we parse something?

static Lisp nlParse(String s) {
  return nlParse(s, true);
}

static Lisp nlParse(String s, boolean unbracket) {
  return nlParse(codeTokens(snlTok(s)), unbracket, null);
}

static Lisp nlParse(List<String> tok) {
  return nlParse(tok, true, null);
}

static Lisp nlParse(List<String> tok, boolean unbracket, List<String> warnings) {
  nlParse_count.incrementAndGet();
  
  class Entry {
    int i;
    Lisp tree;
    String wrapper;
    
    Entry(int i) {
  this.i = i;
      tree = lisp("[]");
    }
    
    Entry(int i, String bracket) {
  this.i = i;
      tree = lisp("[]");
      wrapper = bracket;
    }
    
    Lisp wrapped() {
      Lisp t = nlUnbracket(tree);
      return wrapper == null ? t : lisp(wrapper, t);
    }
  }

  List<Entry> stack = new ArrayList<Entry>();
  stack.add(new Entry(0));
  
  for (int i = 0; i < l(tok); i++) {
    String t = tok.get(i);
    if (eq(t, "[") || eq(t, "(")) {
      stack.add(new Entry(i, eq(t, "(") ? "()" : null));
    } else if (eq(t, "]") || eq(t, ")")) {
      if (l(stack) == 1)
        warn("too many closing brackets", warnings);
      else {
        Entry e = popLast(stack);
        /*if (!bracketsMatch(tok.get(e.i), t))
          warn("non-matching brackets");*/
        last(stack).tree.add(e.wrapped());
      }
    } else
      last(stack).tree.add(t);
  }
  
  while (l(stack) > 1) {
    warn("too many opening brackets", warnings);
    Entry e = popLast(stack);
    last(stack).tree.add(e.wrapped());
  }
  
  Lisp result = last(stack).wrapped();
  return unbracket ? nlUnbracket(result) : result;
}

static String addPrefix(String prefix, String s) {
  return s.startsWith(prefix) ? s : prefix + s;
}
static <A> List<A> subList(List<A> l, int startIndex) {
  return subList(l, startIndex, l(l));
}

static <A> List<A> subList(List<A> l, int startIndex, int endIndex) {
  startIndex = max(0, min(l(l), startIndex));
  endIndex = max(0, min(l(l), endIndex));
  if (startIndex > endIndex) return litlist();
  return l.subList(startIndex, endIndex);
}
  static void set(Object o, String field, Object value) {
    if (o instanceof Class) set((Class) o, field, value);
    else try {
      Field f = set_findField(o.getClass(), field);
      smartSet(f, o, value);
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }
  
  static void set(Class c, String field, Object value) {
    try {
      Field f = set_findStaticField(c, field);
      smartSet(f, null, value);
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }
  
  static Field set_findField(Class<?> c, String field) {
    for (Field f : c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    throw new RuntimeException("Field '" + field + "' not found in " + c.getName());
  }
  
  static Field set_findStaticField(Class<?> c, String field) {
    for (Field f : c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & Modifier.STATIC) != 0)
        return f;
    throw new RuntimeException("Static field '" + field + "' not found in " + c.getName());
  }
static <A> A or(A a, A b) {
  return a != null ? a : b;
}
// split smth like "if * then *" into "if *" and "then *"
// returns null if no split
// now also for NL trees
static List<Lisp> snlSplitOps(Lisp code) {
  List<Lisp> out = new ArrayList<Lisp>();
  
  if (code.is("[]")) {
    // NL
    
    if ((code.size() & 1) != 0) return null;
    for (int i = 0; i < code.size(); i += 2) {
      Lisp op = code.get(i), arg = code.get(i+1);
      if (!op.isLeaf() || !isExtendedIdentifier(op.head)) return null;
      out.add(lisp(op + " *", nlUnbracket(arg)));
    }
    
    return out;
  }
  
  String ops = code.head;
  List<String> tok = codeTokensOnly(javaTok(ops));
  if ((l(tok) & 1) != 0) return null;
  for (int i = 0; i < l(tok); i += 2) {
    String op = tok.get(i);
    if (!isIdentifier(op) || neq("*", tok.get(i+1))) return null;
    out.add(lisp(op + " *", code.get(i/2)));
  }
  //print("splitOps => " + structure(out));
  return out;
}
static boolean match(String pat, String s) {
  return match3(pat, s);
}

static boolean match(String pat, String s, Matches matches) {
  return match3(pat, s, matches);
}

static boolean eqic(String a, String b) {
  if ((a == null) != (b == null)) return false;
  if (a == null) return true;
  return a.equalsIgnoreCase(b);
}
static String slackSnippet(Object contents) {
  if (contents instanceof List) contents = join("\n", (List) contents);
  String s = str(contents);
  //ret "```" + (empty(s) ? "\n" : s) + "```";
  return "```\n" + s + "```";
}
static String getString(Map map, Object key) {
  return map == null ? null : (String) map.get(key);
}

static String getString(List l, int idx) {
  return (String) get(l, idx);
}

static String getString(Object o, Object key) {
  if (o instanceof Map) return getString((Map) o, key);
  if (key instanceof String)
    return (String) get(o, (String) key);
  throw fail("Not a string key: " + getClassName(key));
}
static boolean containsIgnoreCase(List<String> l, String s) {
  for (String x : l)
    if (eqic(x, s))
      return true;
  return false;
}

static boolean containsIgnoreCase(String[] l, String s) {
  for (String x : l)
    if (eqic(x, s))
      return true;
  return false;
}
static String n(long l, String name) {
  return l + " " + (l == 1 ? name : getPlural(name));
}
static boolean startsWithUpperCase(String s) {
  return nempty(s) && Character.isUpperCase(s.charAt(0));
}
static int parseInt(String s) {
  return Integer.parseInt(s);
}
static Object quickExport(Object o, Object dest) { try {
 
  if (o == null || o instanceof String || o instanceof Number) return o;
  
  if (o instanceof List) {
    List l = (List) ( o);
    List destO = new ArrayList(l.size());
    for (int i = 0; i < l.size(); i++)
      destO.add(quickExport(l.get(i), dest));
    return destO;
  }
  
  if (o instanceof Map) {
    Map m = (Map) ( o);
    Map destO = new HashMap();
    for (Object e : ((Map) o).entrySet())
      destO.put(
        quickExport(((Map.Entry) e).getKey(), dest),
        quickExport(((Map.Entry) e).getValue(), dest));
    return destO;
  }
  
  String className = o.getClass().getName();
  if (className.startsWith("main$")) {
    Class destClass = getClass(dest, className);
    //print(o.getClass() + " => " + destClass);
    
    if (o.getClass() == destClass)
      return o; // no export necessary
      
    // actually make a new object(), copy fields
    
    Object destO = nuObject(destClass);
    
    // TODO: superclasses
    Field[] fields = o.getClass().getDeclaredFields();
    for (Field field : fields) {
      if ((field.getModifiers() & Modifier.STATIC) != 0)
        continue;
      field.setAccessible(true);
      Object value = field.get(o);
      setOpt(destO, field.getName(), quickExport(value, dest));
    }
    
    return destO;
  }
  
  // assume it's a shared library object
  return o;

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static <A> A popLast(List<A> l) {
  return liftLast(l);
}
static String lstr(Map map) {
  return str(l(map));
}

static String lstr(List l) {
  return str(l(l));
}

static String lstr(String s) {
  return str(l(s));
}
static boolean equals(Object a, Object b) {
  return a == null ? b == null : a.equals(b);
}
static String nlUnparse(Lisp tree) {
  return nlUnparse(tree, true);
}

static String nlUnparse(Lisp tree, boolean dropOuterBrackets) {
  StringBuilder buf = new StringBuilder();
  nlUnparse(tree, buf, dropOuterBrackets);
  return str(buf);
}

static void nlUnparse(Lisp tree, StringBuilder buf, boolean dropOuterBrackets) {
  if (tree == null) return;
  
  // special classes - Var etc.
  if (tree.getClass() != Lisp.class) {
    buf.append(tree);
    return;
  }
  
  if (tree.isA("[]")) {
    if (!dropOuterBrackets) buf.append("[");
  } else if (tree.isA("()"))
    buf.append("(");
  else {
    if (tree.isLeaf())
      buf.append(tree.head);
    else
      buf.append("?? " + tree);
    return;
  }
  
  for (int i = 0; i < tree.size(); i++) {
    if (i != 0) buf.append(" ");
    nlUnparse(tree.get(i), buf, false);
  }
  
  if(tree.isA("[]")) {
    if (!dropOuterBrackets) buf.append("]");
  } else
    buf.append(")");
}
static Object first(Object list) {
  return ((List) list).isEmpty() ? null : ((List) list).get(0);
}

static <A> A first(List<A> list) {
  return list.isEmpty() ? null : list.get(0);
}

static Lisp simplifySNLTree(Lisp tree) {
  while (tree != null && tree.isA("[]") && tree.size() == 1)
    tree = tree.get(0);
  if (tree == null) return null;
  Lisp lisp = new Lisp(tree.head);
  for (Lisp child : tree)
    lisp.add(simplifySNLTree(child));
  return lisp;
}
static boolean startsWithLetter(String s) {
  return nempty(s) && Character.isLetter(s.charAt(0));
}
static String getPlural(String s) {
  if (s.endsWith("y")) return dropSuffix("y", s) + "ies";
  return s + "s";
}
  static List<String> codeTokensOnly(List<String> tok) {
    List<String> l = new ArrayList<String>();
    for (int i = 1; i < tok.size(); i += 2)
      l.add(tok.get(i));
    return l;
  }
/*
Binding levels (well...):
0 = lowest
1 = arrows (> lowest)
2 = arrowsr (> arrows)
3 = word (> arrows)
4 = juxta, idword, subword (> word)
*/


static String snlParse_rules = "\n  // highest (strongest binding) level \n  <extidentifier> = idword\n  <int> = subword\n  <quoted> = subword\n  // <ucid> = subword\n  \n  // random symbols we'd want to use\n  // (they don't parse if not listed here)\n  ? = symbol\n  : = symbol\n  * = symbol\n  \"=\" = symbol\n  + = symbol\n  , = symbol\n  . = symbol\n  <symbol> = idword\n  \n  <subword> = word\n  <idword> = word\n  \n  // juxtaposition on highest level\n  <word> <word> = juxta\n  <juxta> = word\n  \n  // bracketing takes us to highest level\n  [ <lowest> ] = square\n  ( <lowest> ) = round\n  \n  <square> = subword\n  <round> = subword\n  \n  // < is intermediate\n  <word> = arrowsr\n  <word> > <arrowsr> = realarrowr\n  <realarrowr> = arrowsr\n  \n  <arrowsr> < <arrows> = realarrow\n  <realarrow> = arrows\n  <arrowsr> = arrows\n  \n  = lowest // allow empty here\n  <arrows> = lowest\n";

static Explain snlParse(String input) {
  return explainFull(snlTok(input), snlParse_rules, "lowest");
}

static Lisp nlUnbracket(Lisp tree) {
  while (tree.is("[]", 1))
    tree = tree.get(0);
  return tree;
}
static <A> A liftLast(List<A> l) {
  if (l.isEmpty()) return null;
  int i = l(l)-1;
  A a = l.get(i);
  l.remove(i);
  return a;
}
static boolean isExtendedIdentifier(String s) {
  if (empty(s)) return false;
  for (int i = 0; i < l(s); i++) {
    char c = s.charAt(i);
    if (c != '\'' && !(i == 0 ? Character.isLetter(c) : Character.isLetterOrDigit(c)))
      return false;
  }
  return true;
}
// replacement for class JavaTok
// maybe incomplete, might want to add floating point numbers
// todo also: extended multi-line strings

static List<String> javaTok(String s) {
  List<String> tok = new ArrayList<String>();
  int l = s.length();
  
  int i = 0;
  while (i < l) {
    int j = i;
    char c; String cc;
    
    // scan for whitespace
    while (j < l) {
      c = s.charAt(j);
      cc = s.substring(j, Math.min(j+2, l));
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
        ++j;
      else if (cc.equals("/*")) {
        do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/"));
        j = Math.min(j+2, l);
      } else if (cc.equals("//")) {
        do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0);
      } else
        break;
    }
    
    tok.add(s.substring(i, j));
    i = j;
    if (i >= l) break;
    c = s.charAt(i); // cc is not needed in rest of loop body
    cc = s.substring(i, Math.min(i+2, l));

    // scan for non-whitespace
    if (c == '\'' || c == '"') {
      char opener = c;
      ++j;
      while (j < l) {
        if (s.charAt(j) == opener || s.charAt(j) == '\n') { // end at \n to not propagate unclosed string literal errors
          ++j;
          break;
        } else if (s.charAt(j) == '\\' && j+1 < l)
          j += 2;
        else
          ++j;
      }
    } else if (Character.isJavaIdentifierStart(c))
      do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || "'".indexOf(s.charAt(j)) >= 0)); // for stuff like "don't"
    else if (Character.isDigit(c)) {
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
      if (j < l && s.charAt(j) == 'L') ++j; // Long constants like 1L
    } else if (cc.equals("[[")) {
      do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]"));
      j = Math.min(j+2, l);
    } else if (cc.equals("[=") && i+2 < l && s.charAt(i+2) == '[') {
      do ++j; while (j+2 < l && !s.substring(j, j+3).equals("]=]"));
      j = Math.min(j+3, l);
    } else
      ++j;

    tok.add(s.substring(i, j));
    i = j;
  }
  
  if ((tok.size() % 2) == 0) tok.add("");
  return tok;
}

static List<String> javaTok(List<String> tok) {
  return javaTok(join(tok));
}
static int min(int a, int b) {
  return Math.min(a, b);
}

static double min(double[] c) {
  double x = Double.MAX_VALUE;
  for (double d : c) x = Math.min(x, d);
  return x;
}

static <A> ArrayList<A> litlist(A... a) {
  return new ArrayList<A>(Arrays.asList(a));
}
// This is made for SNL parsing.
// It does NOT recognize multiline strings as these conflict
// with syntax like [[a] [b]].

static List<String> snlTok(String s) {
  List<String> tok = new ArrayList<String>();
  int l = s.length();
  
  int i = 0;
  while (i < l) {
    int j = i;
    char c; String cc;
    
    // scan for whitespace
    while (j < l) {
      c = s.charAt(j);
      cc = s.substring(j, Math.min(j+2, l));
      if (c == ' ' || c == '\t' || c == '\r' || c == '\n')
        ++j;
      else if (cc.equals("/*")) {
        do ++j; while (j < l && !s.substring(j, Math.min(j+2, l)).equals("*/"));
        j = Math.min(j+2, l);
      } else if (cc.equals("//")) {
        do ++j; while (j < l && "\r\n".indexOf(s.charAt(j)) < 0);
      } else
        break;
    }
    
    tok.add(s.substring(i, j));
    i = j;
    if (i >= l) break;
    c = s.charAt(i);
    cc = s.substring(i, Math.min(i+2, l));

    // scan for non-whitespace
    if (c == '\u201C' || c == '\u201D') c = '"'; // normalize quotes
    if (c == '\'' || c == '"') {
      char opener = c;
      ++j;
      while (j < l) {
        char _c = s.charAt(j);
        if (_c == '\u201C' || _c == '\u201D') _c = '"'; // normalize quotes
        if (_c == opener) {
          ++j;
          break;
        } else if (s.charAt(j) == '\\' && j+1 < l)
          j += 2;
        else
          ++j;
      }
      if (j-1 >= i+1) {
        tok.add(opener + s.substring(i+1, j-1) + opener);
        i = j;
        continue;
      }
    } else if (Character.isJavaIdentifierStart(c))
      do ++j; while (j < l && (Character.isJavaIdentifierPart(s.charAt(j)) || s.charAt(j) == '\'')); // for things like "this one's"
    else if (Character.isDigit(c))
      do ++j; while (j < l && Character.isDigit(s.charAt(j)));
    /*else if (cc.equals("[[")) {
      do ++j; while (j+1 < l && !s.substring(j, j+2).equals("]]"));
      j = Math.min(j+2, l);
    }*/ else if (s.substring(j, Math.min(j+3, l)).equals("..."))
      j += 3;
    else if (c == '$' || c == '#')
      do ++j; while (j < l && Character.isLetterOrDigit(s.charAt(j)));
    else
      ++j;

    tok.add(s.substring(i, j));
    i = j;
  }
  
  if ((tok.size() % 2) == 0) tok.add("");
  return tok;
}

static List<String> codeTokens(List<String> tok) {
  return codeTokensOnly(tok);
}
static int max(int a, int b) {
  return Math.max(a, b);
}

static long max(int a, long b) {
  return Math.max((long) a, b);
}

static long max(long a, long b) {
  return Math.max(a, b);
}

static double max(int a, double b) {
  return Math.max((double) a, b);
}

static int max(Collection<Integer> c) {
  int x = Integer.MIN_VALUE;
  for (int i : c) x = max(x, i);
  return x;
}

static double max(double[] c) {
  if (c.length == 0) return Double.MIN_VALUE;
  double x = c[0];
  for (int i = 1; i < c.length; i++) x = Math.max(x, c[i]);
  return x;
}

  // class Matches is added by #752
 
  static boolean match3(String pat, String s) {
    return match3(pat, s, null);
  }
  
  static boolean match3(String pat, String s, Matches matches) {
    if (s == null) return false;
    return match3(pat, parse3(s), matches);
  }
    
  static boolean match3(String pat, List<String> toks, Matches matches) {
    List<String> tokpat = parse3(pat);
    return match3(tokpat,toks,matches);
  }

  static boolean match3(List<String> tokpat, List<String> toks, Matches matches) {

    String[] m = match2(tokpat, toks);
    //print(structure(tokpat) + " on " + structure(toks) + " => " + structure(m));
    if (m == null)
      return false;
    else {
      if (matches != null) matches.m = m;
      return true;
    }
  }
static Class mc() {
  return getMainClass();
}
static boolean neq(Object a, Object b) {
  return !eq(a, b);
}
static boolean warn_on = false;

static void warn(String s) {
  if (warn_on)
    print("Warn: " + s);
}

static void warn(String s, List<String> warnings) {
  warn(s);
  if (warnings != null)
    warnings.add(s);
}
  static <A> List<A> concatLists(List<A>... lists) {
    List<A> l = new ArrayList<A>();
    for (List<A> list : lists)
      if (list != null)
        l.addAll(list);
    return l;
  }

  static <A> List<A> concatLists(List<List<A>> lists) {
    List<A> l = new ArrayList<A>();
    for (List<A> list : lists)
      if (list != null)
        l.addAll(list);
    return l;
  }

static Object nuObject(String className, Object... args) { try {
 
  return nuObject(Class.forName(className), args);

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}

static Object nuObject(Class c, Object... args) { try {
 
  Constructor m = nuObject_findConstructor(c, args);
  m.setAccessible(true);
  return m.newInstance(args);

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}

static Constructor nuObject_findConstructor(Class c, Object... args) {
  for (Constructor m : c.getDeclaredConstructors()) {
    if (!nuObject_checkArgs(m.getParameterTypes(), args, false))
      continue;
    return m;
  }
  throw new RuntimeException("Constructor with " + args.length + " matching parameter(s) not found in " + c.getName());
}

 static boolean nuObject_checkArgs(Class[] types, Object[] args, boolean debug) {
    if (types.length != args.length) {
      if (debug)
        System.out.println("Bad parameter length: " + args.length + " vs " + types.length);
      return false;
    }
    for (int i = 0; i < types.length; i++)
      if (!(args[i] == null || isInstanceX(types[i], args[i]))) {
        if (debug)
          System.out.println("Bad parameter " + i + ": " + args[i] + " vs " + types[i]);
        return false;
      }
    return true;
  }
static String getClassName(Object o) {
  return o == null ? "null" : o.getClass().getName();
}
  public static String fromLines(List<String> lines) {
    StringBuilder buf = new StringBuilder();
    if (lines != null)
      for (String line : lines)
        buf.append(line).append('\n');
    return buf.toString();
  }
static String substring(String s, int x) {
  return safeSubstring(s, x);
}

static String substring(String s, int x, int y) {
  return safeSubstring(s, x, y);
}
  static String repeat(char c, int n) {
    n = max(n, 0);
    char[] chars = new char[n];
    for (int i = 0; i < n; i++)
      chars[i] = c;
    return new String(chars);
  }

  static <A> List<A> repeat(A a, int n) {
    List<A> l = new ArrayList<A>();
    for (int i = 0; i < n; i++)
      l.add(a);
    return l;
  }

static void smartSet(Field f, Object o, Object value) throws Exception {
  f.setAccessible(true);
  
  // take care of common case (long to int)
  if (f.getType() == int.class && value instanceof Long)
    value = ((Long) value).intValue();
    
  f.set(o, value);
}
  static void setOpt(Object o, String field, Object value) {
    if (o instanceof Class) setOpt((Class) o, field, value);
    else try {
      Field f = setOpt_findField(o.getClass(), field);
      if (f != null)
        smartSet(f, o, value);
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }
  
  static void setOpt(Class c, String field, Object value) {
    try {
      Field f = setOpt_findStaticField(c, field);
      if (f != null)
        smartSet(f, null, value);
    } catch (Exception e) {
      throw new RuntimeException(e);
    }
  }
  
  static Field setOpt_findField(Class<?> c, String field) {
    for (Field f : c.getDeclaredFields())
      if (f.getName().equals(field))
        return f;
    return null;
  }
  
  static Field setOpt_findStaticField(Class<?> c, String field) {
    for (Field f : c.getDeclaredFields())
      if (f.getName().equals(field) && (f.getModifiers() & Modifier.STATIC) != 0)
        return f;
    return null;
  }

// hopefully covers all cases :)
static String safeSubstring(String s, int x, int y) {
  if (s == null) return null;
  if (x < 0) x = 0;
  if (x > s.length()) return "";
  if (y < x) y = x;
  if (y > s.length()) y = s.length();
  return s.substring(x, y);
}

static String safeSubstring(String s, int x) {
  return safeSubstring(s, x, l(s));
}

static Explain explainFull(String input, String rules, String className) {
  return explainFull(javaTok(input), rules, className);
}
  
static Explain explainFull(List<String> tok, String rules, String className) {
  Object parseResult = parse1(tok, rules);
  List e = (List) ( call(parseResult, "explainFull", className));
  if (e == null) return null;
  return new Explain(parseResult, e);
}

  static List<String> parse3(String s) {
    return dropPunctuation(javaTokPlusPeriod(s));
  }
static Class getMainClass() { try {
 
  return Class.forName("main");

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}

static Class getMainClass(Object o) { try {
 
  return (o instanceof Class ? (Class) o : o.getClass()).getClassLoader().loadClass("main");

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
// match2 matches multiple "*" (matches a single token) wildcards and zero or one "..." wildcards (matches multiple tokens)

static String[] match2(List<String> pat, List<String> tok) {
  // standard case (no ...)
  int i = pat.indexOf("...");
  if (i < 0) return match2_match(pat, tok);
  
  pat = new ArrayList<String>(pat); // We're modifying it, so copy first
  pat.set(i, "*");
  while (pat.size() < tok.size()) {
    pat.add(i, "*");
    pat.add(i+1, ""); // doesn't matter
  }
  
  return match2_match(pat, tok);
}

static String[] match2_match(List<String> pat, List<String> tok) {
  List<String> result = new ArrayList<String>();
  if (pat.size() != tok.size()) {
    /*if (debug)
      print("Size mismatch: " + structure(pat) + " vs " + structure(tok));*/
    return null;
  }
  for (int i = 1; i < pat.size(); i += 2) {
    String p = pat.get(i), t = tok.get(i);
    /*if (debug)
      print("Checking " + p + " against " + t);*/
    if (eq(p, "*"))
      result.add(t);
    else if (!equalsIgnoreCase(unquote(p), unquote(t))) // bold change - match quoted and unquoted now
      return null;
  }
  return result.toArray(new String[result.size()]);
}

static String dropSuffix(String suffix, String s) {
  return s.endsWith(suffix) ? s.substring(0, l(s)-l(suffix)) : s;
}

static boolean equalsIgnoreCase(String a, String b) {
  return a == null ? b == null : a.equalsIgnoreCase(b);
}
static Object parse1_parser;

static Object parse1(String text, String rules) {
  return parse1(javaTok(text), rules);
}

// only parse, no explain
static synchronized Object parse1(List<String> tok, String rules) {
  if (parse1_parser == null)
    parse1_parser = run_overBot(/*"#1002472"*/ "#1002719");
  //setOpt(parse1_parser, "debug", true);
  return call(parse1_parser, "parse", tok, rules);
}
static List<String> dropPunctuation_keep = litlist("*", "<", ">");

static List<String> dropPunctuation(List<String> tok) {
  tok = new ArrayList<String>(tok);
  for (int i = 1; i < tok.size(); i += 2) {
    String t = tok.get(i);
    if (t.length() == 1 && !Character.isLetter(t.charAt(0)) && !Character.isDigit(t.charAt(0)) && !dropPunctuation_keep.contains(t)) {
      tok.set(i-1, tok.get(i-1) + tok.get(i+1));
      tok.remove(i);
      tok.remove(i);
      i -= 2;
    }
  }
  return tok;
}

static String dropPunctuation(String s) {
  return join(dropPunctuation(nlTok(s)));
}

static Class run_overBot(String progID) {
  Class main = hotwire_overBot(progID);
  callMain(main);
  return main;
}
static List<String> nlTok(String s) {
  return javaTokPlusPeriod(s);
}

static Class<?> hotwire_overBot(String progID) { try {
 
  String compilerBot = "Compiler Bot with caching!";
  startBot(compilerBot, "#1002203");
  
  String ss = "please compile this javax snippet: *";
  print("Sending to compiler bot: " + ss);
  String s = sendToLocalBot_cached(compilerBot, ss, progID);
  Matches m = new Matches();
  print(s);
  assertTrue("Compiler Bot response: " + s, match("ok, *", s, m));
  String jarPath = m.unq(0);
  File jar = new File(jarPath);
  assertTrue(jar.getAbsolutePath(), jar.isFile());
  
  // collect urls (program + libraries)
  
  List<URL> urls = litlist(jar.toURI().toURL());
  String dehlibs = unnull(loadTextFileFromZip(jar, "libraries"));
  
  Matcher matcher = Pattern.compile("\\d+").matcher(dehlibs);
  while (matcher.find()) {
    String libID = matcher.group();
    urls.add(loadLibrary(libID).toURI().toURL());
  }

  // make class loader
  URLClassLoader classLoader = new URLClassLoader(urls.toArray(new URL[l(urls)]));

  // load & return main class
  Class<?> theClass = classLoader.loadClass("main");
  
  Class j = getJavaX();
  
  String src = loadTextFileFromZip(jar, "main.java");
  call(j, "registerSourceCode", theClass, src);
  
  synchronized(j) { // hopefully this goes well...
    call(j, "setVars", theClass, progID);
    callOpt(j, "addInstance", progID, theClass);
  }
  
  synchronized(StringBuffer.class) {
    Object print_log = get(getMainClass(), "print_log");
    assertTrue(print_log != null);
    setOpt(theClass, "print_log", print_log);
  }

  return theClass;

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static void callMain(Object c, String... args) {
  callOpt(c, "main", new Object[] {args});
}

static void assertTrue(Object o) {
  assertEquals(true, o);
}
  
static boolean assertTrue(String msg, boolean b) {
  if (!b)
    fail(msg);
  return b;
}

static boolean assertTrue(boolean b) {
  if (!b)
    fail("oops");
  return b;
}
static Class __javax;

static Class getJavaX() {
  return __javax;
}
static Map<String, String> startBot_assignments = new TreeMap<String, String>();

static void startBot(String botName, String botID) {
  DialogIO bot = newFindBot(botName);
  if (bot != null)
    bot.close();
  else {
    print("Bot " + quote(botName) + " not found. Starting " + botID);
    javaxBot(botID);
    waitForBotStartUp(botName);
  }
}

static void startBot(String botIDOrName) {
  String botID = startBot_assignments.get(botIDOrName);
  if (botID != null)
    startBot(botIDOrName, botID);
  else {
    String botName = getBotNameFromSnippet(botIDOrName);
    if (botName == null) fail("Bot name not found in source of " + botID);
    startBot(botName, botIDOrName);
  }
}

static File loadLibrary(String snippetID) {
  return loadBinarySnippet(snippetID);
}
static String loadTextFileFromZip(File inZip, String fileName) {
  return loadTextFileFromZipFile(inZip, fileName);
}
static String sendToLocalBot_cached(String botName, String s, Object... args) {
  DialogIO io = newFindBot(botName);
  if (io == null)
    fail("Bot not found: " + botName);
  try {
    return io.ask(s, args);
  } finally {
    io.close();
  }
}

static int newFindBot_botVM;

static synchronized DialogIO newFindBot(String name) {
  if (newFindBot_botVM == 0) {
    print("Looking for Bot VM.");
    List<ProgramScan.Program> botVMs = quickBotScan("This is a JavaX VM. Bot VM.");
    if (!botVMs.isEmpty()) {
      newFindBot_botVM = botVMs.get(0).port;
      print("Bot VM is at port " + newFindBot_botVM + ".");
    }
  }
  
  if (newFindBot_botVM != 0) {
    DialogIO io = talkTo(newFindBot_botVM);
    String q = format("has bot *", name);
    String s = io.ask(q);
    //print(format("Answer of Bot VM to *: *", q, s));
    
    if (match("yes", s)) {
      io = talkToSubBot(name, io);
      call(io, "pushback", "?"); // put some hello string in (yes, this should be improved.)
      return io;
    }
  }
  
  return findBot(name);
}
static void javaxBot(String botID) {
  startBotVM();
  if (injectTo("Bot VM", botID) == null)
    fail("Couldn't inject to Bot VM");
    //nohupJavax(botID);
}
static long waitForBotStartUp_timeoutSeconds = 60;

// returns address or fails
static String waitForBotStartUp(String botName) {
  for (int i = 0; i < waitForBotStartUp_timeoutSeconds; i++) {
    sleepSeconds(i == 0 ? 0 : 1);
    String addr = getBotAddress(botName);
    if (addr != null)
      return addr;
  }
  throw fail("Bot not found: " + quote(botName));
}
static File loadBinarySnippet(String snippetID) { try {
 
  long id = parseSnippetID(snippetID);
  File f = DiskSnippetCache_getLibrary(id);
  if (f == null) {
    byte[] data = loadDataSnippetImpl(snippetID);
    DiskSnippetCache_putLibrary(id, data);
    f = DiskSnippetCache_getLibrary(id);
  }
  return f;

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static void assertEquals(Object x, Object y) {
  assertEquals(null, x, y);
}

static void assertEquals(String msg, Object x, Object y) {
  if (!(x == null ? y == null : x.equals(y)))
    fail((msg != null ? msg + ": " : "") + structure(x) + " != " + structure(y));
}
  // covers the common cases
  static String getBotNameFromSnippet(String programID) { try {
 
    String src = loadSnippet(programID);
    List<String> tok = javaTok(src);
    String[] m;
    for (String pat : litlist(
      "new Android3(*",
      "makeAndroid(*", "makeAndroid3(*", "makeSilentAndroid(*",
      "addToMultiPort(*")) {
      m = find2(javaTok(pat), tok);
      if (m != null && isQuoted(m[0])) return unquote(m[0]);
    }
    return null;
  
} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static String loadTextFileFromZipFile(File inZip, String fileName) { try {
 
  ZipFile zip = new ZipFile(inZip);
  try {
    ZipEntry entry = zip.getEntry(fileName);
    if (entry == null)
      //fail("Entry " + fileName + " not found in zip file: " + inZip.getAbsolutePath());
      return null;
      
    InputStream fin = zip.getInputStream(entry);
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    copyStream(fin, baos);
    fin.close();
    return fromUTF8(baos.toByteArray());
  } finally {
    zip.close();
  }

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}

static class Injection {
  int vmPort;
  String injectionID;
}

static Injection injectTo(int vmPort, String progID) {
  return injectTo(String.valueOf(vmPort), progID);
}

static Injection injectTo(String vmName, String progID) {
  String line = format3("Please inject program *.", progID);
  
  DialogIO injectionPoint = findBot(isInteger(vmName) ? vmName : "This is a JavaX VM. " + vmName);
  if (injectionPoint == null) return null;
  try {
    injectionPoint.readLine();
    String answer = injectionPoint.askLoudly(line);
    Matches m = new Matches();
    if (match3("OK. Injection ID: *", answer, m)) {
      Injection i = new Injection();
      i.vmPort = injectionPoint.getSocket().getPort();
      i.injectionID = m.unq(0);
      return i;
    }
    throw fail(answer);
  } finally {
    injectionPoint.close();
  }
}
static DialogIO talkTo(int port) {
  return talkTo("localhost", port);
}

static DialogIO talkTo(String ip, int port) { try {
 
  final Socket s = new Socket(ip, port);    
  //print("Talking to " + ip + ":" + port);

  final Writer w = new OutputStreamWriter(s.getOutputStream(), "UTF-8");
  final BufferedReader in = new BufferedReader(new InputStreamReader(s.getInputStream(), "UTF-8"));
  return new DialogIO() {
    boolean isLocalConnection() {
      return s.getInetAddress().isLoopbackAddress();
    }
    
    boolean isStillConnected() {
      return !(eos || s.isClosed());
    }
    
    void sendLine(String line) { try {
 
      w.write(line + "\n");
      w.flush();
    
} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
    
    String readLineImpl() { try {
 
      return in.readLine();
    
} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
    
    void close() {
      try {
        s.close();
      } catch (IOException e) {
        // whatever
      }
    }
    
    Socket getSocket() {
      return s;
    }
  };

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static DialogIO talkToSubBot(final long vport, final DialogIO io) {
  return talkToSubBot(String.valueOf(vport), io);
}

static DialogIO talkToSubBot(final String subBot, final DialogIO io) {
  if (subBot == null) return io;
  
  return new DialogIO() {
    // delegate all but sendLine
    boolean isStillConnected() { return io.isStillConnected(); }
    String readLineImpl() { return io.readLineImpl(); }
    boolean isLocalConnection() { return io.isLocalConnection(); }
    Socket getSocket() { return io.getSocket(); }
    void close() { io.close(); }

    void sendLine(String line) {
      io.sendLine(format3("please forward to bot *: *", subBot, line));
    }
  };
}
  
  // Data files are immutable, use centralized cache
public static File DiskSnippetCache_getLibrary(long snippetID) throws IOException {
  File file = new File(getGlobalCache(), "data_" + snippetID + ".jar");
  return file.exists() ? file : null;
}

public static void DiskSnippetCache_putLibrary(long snippetID, byte[] data) throws IOException {
  saveBinaryFile(new File(getGlobalCache(), "data_" + snippetID).getPath() + ".jar", data);
}

static byte[] loadDataSnippetImpl(String snippetID) throws IOException {
  byte[] data;
  try {
    URL url = new URL("http://eyeocr.sourceforge.net/filestore/filestore.php?cmd=serve&file=blob_"
      + parseSnippetID(snippetID) + "&contentType=application/binary");
    System.err.println("Loading library: " + url);
    try {
      data = loadBinaryPage(url.openConnection());
    } catch (IOException e) {
      data = null;
    }
    
    if (data == null || data.length == 0) {
      url = new URL("http://data.tinybrain.de/blobs/"
        + parseSnippetID(snippetID));
      System.err.println("Loading library: " + url);
      data = loadBinaryPage(url.openConnection());
    }
    System.err.println("Bytes loaded: " + data.length);
  } catch (FileNotFoundException e) {
    throw new IOException("Binary snippet #" + snippetID + " not found or not public");
  }
  return data;
}
// We dropped the "***" support here (use match3 for that)

static String[] find2(List<String> pat, List<String> tok) {
  for (int idx = 0; idx < tok.size(); idx += 2) {
    String[] result = find2(pat, tok, idx);
    if (result != null) return result;
  }
  return null;
}

static String[] find2(List<String> pat, List<String> tok, int idx) {
  if (idx+pat.size() > tok.size())
    return null;
  List<String> result = new ArrayList<String>();
  for (int i = 1; i < pat.size(); i += 2) {
    String p = pat.get(i), t = tok.get(idx+i);
    if (eq(p, "*"))
      result.add(t);
    else if (!p.equalsIgnoreCase(t))
      return null;
  }
  return toStringArray(result);
}

static Map<String, Integer> findBot_cache = new TreeMap<String, Integer>();
static int findBot_timeout = 5000;

static DialogIO findBot(String searchPattern) {
  // first split off sub-bot suffix
  String subBot = null;
  int i = searchPattern.indexOf('/');
  if (i >= 0 && (isJavaIdentifier(searchPattern.substring(0, i)) || isInteger(searchPattern.substring(0, i)))) {
    subBot = searchPattern.substring(i+1);
    searchPattern = searchPattern.substring(0, i);
    if (!isInteger(searchPattern))
      searchPattern = "Multi-Port at " + searchPattern + ".";
  }
  
  // assume it's a port if it's an integer
  if (isInteger(searchPattern))
    return talkToSubBot(subBot, talkTo(parseInt(searchPattern)));
    
  if (eq(searchPattern, "remote"))
    return talkToSubBot(subBot, talkTo("second.tinybrain.de", 4999));
    
  Integer port = findBot_cache.get(searchPattern);
  if (port != null) try {
    DialogIO io = talkTo("localhost", port);
    io.waitForLine(/*findBot_timeout*/); // TODO: implement
    String line = io.readLineNoBlock();
    if (indexOfIgnoreCase(line, searchPattern) == 0) {
      call(io, "pushback", line); // put hello string back in
      return talkToSubBot(subBot, io);
    }
  } catch (Exception e) {
    e.printStackTrace();
  }
  
  List<ProgramScan.Program> bots = quickBotScan();
  
  // find top-level bots
  for (ProgramScan.Program p : bots) {
    if (indexOfIgnoreCase(p.helloString, searchPattern) == 0) { // strict matching - start of hello string only, but case-insensitive
      findBot_cache.put(searchPattern, p.port);
      return talkToSubBot(subBot, talkTo("localhost", p.port));
    }
  }
  
  // find sub-bots
  for (ProgramScan.Program p : bots) {
    String botName = firstPartOfHelloString(p.helloString);
    boolean isVM = startsWithIgnoreCase(p.helloString, "This is a JavaX VM.");
    boolean shouldRecurse = startsWithIgnoreCase(botName, "Multi-Port") || isVM;
        
    if (shouldRecurse) try {
      Map<Number, String> subBots = (Map) unstructure(sendToLocalBot(p.port, "list bots"));
      for (Number vport : subBots.keySet()) {
        String name = subBots.get(vport);
        if (startsWithIgnoreCase(name, searchPattern))
          return talkToSubBot(vport.longValue(), talkTo("localhost", p.port));
      }
    } catch (Exception e) { e.printStackTrace(); }
  }
        
  return null;
}
static int getBotAddress_timeout = 5000;

static String getBotAddress(String searchPattern) {
  String subBot = "";
  int i = searchPattern.indexOf('/');
  if (i >= 0 && (isJavaIdentifier(searchPattern.substring(0, i)) || isInteger(searchPattern.substring(0, i)))) {
    subBot = searchPattern.substring(i);
    searchPattern = searchPattern.substring(0, i);
    if (!isInteger(searchPattern))
      searchPattern = "Multi-Port at " + searchPattern + ".";
  }
  
  // assume it's a port if it's an integer
  if (isInteger(searchPattern))
    return searchPattern + subBot;
    
  Integer port = findBot_cache.get(searchPattern);
  if (port != null) try {
    DialogIO io = talkTo("localhost", port);
    try {
      io.waitForLine(/*getBotAddress_timeout*/); // TODO: implement
      String line = io.readLineNoBlock();
      if (startsWithIgnoreCase(line, searchPattern))
        return port + subBot;
    } finally {
      io.close();
    }
  } catch (Exception e) {
    e.printStackTrace();
  }
  
  List<ProgramScan.Program> bots = quickBotScan();
  
  // find top-level bots
  for (ProgramScan.Program p : bots) {
    if (indexOfIgnoreCase(p.helloString, searchPattern) == 0) { // strict matching - start of hello string only, but case-insensitive
      return p.port + subBot;
    }
  }
  
  // find sub-bots
  for (ProgramScan.Program p : bots) {
    String botName = firstPartOfHelloString(p.helloString);
    boolean isVM = startsWithIgnoreCase(p.helloString, "This is a JavaX VM.");
    boolean shouldRecurse = startsWithIgnoreCase(botName, "Multi-Port") || isVM;
        
    if (shouldRecurse) try {
      Map<Number, String> subBots = (Map) unstructure(sendToLocalBot(p.port, "list bots"));
      for (Number vport : subBots.keySet()) {
        String name = subBots.get(vport);
        if (startsWithIgnoreCase(name, searchPattern))
          return p.port + "/" + vport;
      }
    } catch (Exception e) { e.printStackTrace(); }
  }
        
  return null;
}
static void sleepSeconds(long s) {
  if (s > 0) sleep(s*1000);
}
static List<ProgramScan.Program> quickBotScan() {
  return ProgramScan.quickBotScan();
}

static List<ProgramScan.Program> quickBotScan(int[] preferredPorts) {
  return ProgramScan.quickBotScan(preferredPorts);
}

static List<ProgramScan.Program> quickBotScan(String searchPattern) {
  List<ProgramScan.Program> l = new ArrayList<ProgramScan.Program>();
  for (ProgramScan.Program p : ProgramScan.quickBotScan())
    if (indexOfIgnoreCase(p.helloString, searchPattern) == 0)
      l.add(p);
  return l;
}

public static long parseSnippetID(String snippetID) {
  long id = Long.parseLong(shortenSnippetID(snippetID));
  if (id == 0) fail("0 is not a snippet ID");
  return id;
}
  static boolean preferCached = false;

  public static String loadSnippet(String snippetID) {
    try {
      return loadSnippet(parseSnippetID(snippetID), preferCached);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }

  public static String loadSnippet(String snippetID, boolean preferCached) throws IOException {
    return loadSnippet(parseSnippetID(snippetID), preferCached);
  }

  public static String loadSnippet(long snippetID, boolean preferCached) throws IOException {
    String text = getSnippetFromBossBot(snippetID);
    if (text != null) return text;
    
    initSnippetCache();
    text = DiskSnippetCache_get(snippetID);
    
    if (preferCached && text != null)
      return text;
    
    try {
      if (text != null) System.err.println("md5: " + md5(text));
      URL url = new URL("http://tinybrain.de:8080/getraw.php?id=" + snippetID + "&utf8=1");
      text = loadPage(url);
    } catch (RuntimeException e) {
      e.printStackTrace();
      throw new IOException("Snippet #" + snippetID + " not found or not public");
    }

    try {
      initSnippetCache();
      DiskSnippetCache_put(snippetID, text);
    } catch (IOException e) {
      System.err.println("Minor warning: Couldn't save snippet to cache ("  + DiskSnippetCache_getDir() + ")");
    }

    return text;
  }

  static File DiskSnippetCache_dir;

  public static void initDiskSnippetCache(File dir) {
    DiskSnippetCache_dir = dir;
    dir.mkdirs();
  }

  public static synchronized String DiskSnippetCache_get(long snippetID) throws IOException {
    return loadTextFile(DiskSnippetCache_getFile(snippetID).getPath(), null);
  }

  private static File DiskSnippetCache_getFile(long snippetID) {
    return new File(DiskSnippetCache_dir, "" + snippetID);
  }

  public static synchronized void DiskSnippetCache_put(long snippetID, String snippet) throws IOException {
    saveTextFile(DiskSnippetCache_getFile(snippetID).getPath(), snippet);
  }

  public static File DiskSnippetCache_getDir() {
    return DiskSnippetCache_dir;
  }

  public static void initSnippetCache() {
    if (DiskSnippetCache_dir == null)
      initDiskSnippetCache(new File(System.getProperty("user.home"), ".tinybrain/snippet-cache"));
  }
  
static void startBotVM() {
  startBotSeparateVM("This is a JavaX VM. Bot VM.", "#1001710");
}
static String fromUTF8(byte[] bytes) {
  return fromUtf8(bytes);
}
public static void copyStream(InputStream in, OutputStream out) throws IOException {
  byte[] buf = new byte[65536];
  while (true) {
    int n = in.read(buf);
    if (n <= 0) return;
    out.write(buf, 0, n);
  }
}

static String shortenSnippetID(String snippetID) {
  if (snippetID.startsWith("#"))
    snippetID = snippetID.substring(1);
  String httpBlaBla = "http://tinybrain.de/";
  if (snippetID.startsWith(httpBlaBla))
    snippetID = snippetID.substring(httpBlaBla.length());
  return "" + parseLong(snippetID);
}
static class DynamicObject {
  String className;
  Map<String, Object> fieldValues = new TreeMap<String, Object>();
}

static Object unstructure(String text) {
  return unstructure(text, false);
}

// actually it's now almost the same as jsonDecode :)
static Object unstructure(String text, final boolean allDynamic) {
  final List<String> tok = javaTok(text);
  
  class X {
    int i = 1;

    Object parse() {
      String t = tok.get(i);
      if (t.startsWith("\"")) {
        String s = unquote(tok.get(i));
        i += 2;
        return s;
      }
      if (t.equals("hashset"))
        return parseHashSet();
      if (t.equals("treeset"))
        return parseTreeSet();
      if (t.equals("hashmap"))
        return parseHashMap();
      if (t.equals("{"))
        return parseMap();
      if (t.equals("["))
        return parseList();
      if (t.equals("array"))
        return parseArray();
      if (t.equals("class"))
        return parseClass();
      if (t.equals("bigint"))
        return parseBigInt();
      if (t.equals("d"))
        return parseDouble();
      if (t.equals("l"))
        return parseLisp();
      if (t.equals("null")) {
        i += 2; return null;
      }
      if (t.equals("false")) {
        i += 2; return false;
      }
      if (t.equals("true")) {
        i += 2; return true;
      }
      if (t.equals("-")) {
        t = tok.get(i+2);
        i += 4;
        t = dropSuffix("L", t);
        long l = -Long.parseLong(t);
        return l == (int) l ? (int) l : l;
      }
      if (isInteger(t) || isLongConstant(t)) {
        i += 2;
        t = dropSuffix("L", t);
        long l = Long.parseLong(t);
        return l == (int) l ? (int) l : l;
      }
      if (isJavaIdentifier(t)) {
        Class c = allDynamic ? null : findClass(t);
        DynamicObject dO = null;
        Object o = null;
        if (c != null)
          o = nuObject(c);
        else {
          dO = new DynamicObject();
          dO.className = t;
        }
        i += 2;
        if (i < tok.size() && tok.get(i).equals("(")) {
          consume("(");
          while (!tok.get(i).equals(")")) {
            // It's like parsing a map.
            //Object key = parse();
            //if (tok.get(i).equals(")"))
            //  key = onlyField();
            String key = unquote(tok.get(i));
            i += 2;
            consume("=");
            Object value = parse();
            if (o != null)
              setOpt(o, key, value);
            else
              dO.fieldValues.put(key, value);
            if (tok.get(i).equals(",")) i += 2;
          }
          consume(")");
        }
        return o != null ? o : dO;
      }
      throw new RuntimeException("Unknown token " + (i+1) + ": " + t);
    }
    
    Object parseSet(Set set) {
      set.addAll((List) parseList());
      return set;
    }
    
    Object parseLisp() {
      consume("l");
      consume("(");
      List list = new ArrayList();
      while (!tok.get(i).equals(")")) {
        list.add(parse());
        if (tok.get(i).equals(",")) i += 2;
      }
      consume(")");
      return newObject("main$Lisp", (String) list.get(0), subList(list, 1));
    }
    
    Object parseList() {
      consume("[");
      List list = new ArrayList();
      while (!tok.get(i).equals("]")) {
        list.add(parse());
        if (tok.get(i).equals(",")) i += 2;
      }
      consume("]");
      return list;
    }
    
    Object parseArray() {
      consume("array");
      consume("{");
      List list = new ArrayList();
      while (!tok.get(i).equals("}")) {
        list.add(parse());
        if (tok.get(i).equals(",")) i += 2;
      }
      consume("}");
      return list.toArray();
    }
    
    Object parseClass() {
      consume("class");
      consume("(");
      String name = tok.get(i);
      i += 2;
      consume(")");
      Class c = allDynamic ? null : findClass(name);
      if (c != null) return c;
      DynamicObject dO = new DynamicObject();
      dO.className = "java.lang.Class";
      dO.fieldValues.put("name", name);
      return dO;
    }
    
    Object parseBigInt() {
      consume("bigint");
      consume("(");
      String val = tok.get(i);
      i += 2;
      if (eq(val, "-")) {
        val = "-" + tok.get(i);
        i += 2;
      }
      consume(")");
      return new BigInteger(val);
    }
    
    Object parseDouble() {
      consume("d");
      consume("(");
      String val = unquote(tok.get(i));
      i += 2;
      consume(")");
      return Double.parseDouble(val);
    }
    
    Object parseHashMap() {
      consume("hashmap");
      return parseMap(new HashMap());
    }
    
    Object parseHashSet() {
      consume("hashset");
      return parseSet(new HashSet());
    }
    
    Object parseTreeSet() {
      consume("treeset");
      return parseSet(new TreeSet());
    }
    
    Object parseMap() {
      return parseMap(new TreeMap());
    }
    
    Object parseMap(Map map) {
      consume("{");
      while (!tok.get(i).equals("}")) {
        Object key = unstructure(tok.get(i));
        i += 2;
        consume("=");
        Object value = parse();
        map.put(key, value);
        if (tok.get(i).equals(",")) i += 2;
      }
      consume("}");
      return map;
    }
    
    void consume(String s) {
      if (!tok.get(i).equals(s)) {
        String prevToken = i-2 >= 0 ? tok.get(i-2) : "";
        String nextTokens = join(tok.subList(i, Math.min(i+4, tok.size())));
        fail(quote(s) + " expected: " + prevToken + " " + nextTokens + " (" + i + "/" + tok.size() + ")");
      }
      i += 2;
    }
  }
  
  return new X().parse();
}
static void sleep(long ms) {
  try {
    Thread.sleep(ms);
  } catch (Exception e) { throw new RuntimeException(e); }
}

static void sleep() { try {
 
  print("Sleeping.");
  synchronized(main.class) { main.class.wait(); }

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
  static ThreadLocal<String> loadPage_charset = new ThreadLocal<String>();

  public static String loadPageSilently(String url) {
    try {
      return loadPageSilently(new URL(loadPage_preprocess(url)));
    } catch (IOException e) { throw new RuntimeException(e); }
  }

  public static String loadPageSilently(URL url) {
    try {
      IOException e = null;
      for (int tries = 0; tries < 60; tries++)
        try {
          URLConnection con = url.openConnection();
          return loadPage(con, url);
        } catch (IOException _e) {
          e = _e;
          print("Retrying because of: " + e);
          sleepSeconds(1);
        }
      throw e;
    } catch (IOException e) { throw new RuntimeException(e); }
  }

  static String loadPage_preprocess(String url) {  
    if (url.startsWith("tb/"))
      url = "tinybrain.de:8080/" + url;
    if (url.indexOf("://") < 0)
      url = "http://" + url;
    return url;
  }
  
  public static String loadPage(String url) {
    try {
      return loadPage(new URL(loadPage_preprocess(url)));
    } catch (IOException e) { throw new RuntimeException(e); }
  }
  
  public static String loadPage(URL url) {
    print("Loading: " + url.toExternalForm());
    return loadPageSilently(url);
  }

  public static String loadPage(URLConnection con, URL url) throws IOException {
    String contentType = con.getContentType();
    if (contentType == null)
      throw new IOException("Page could not be read: " + url);
    //print("Content-Type: " + contentType);
    String charset = loadPage_charset.get();
    if (charset == null) charset = loadPage_guessCharset(contentType);
    Reader r = new InputStreamReader(con.getInputStream(), charset);
    StringBuilder buf = new StringBuilder();
    while (true) {
      int ch = r.read();
      if (ch < 0)
        break;
      //Log.info("Chars read: " + buf.length());
      buf.append((char) ch);
    }
    return buf.toString();
  }
  
  static String loadPage_guessCharset(String contentType) {
    Pattern p = Pattern.compile("text/[a-z]+;\\s+charset=([^\\s]+)\\s*");
    Matcher m = p.matcher(contentType);
    /* If Content-Type doesn't match this pre-conception, choose default and hope for the best. */
    return m.matches() ? m.group(1) : "ISO-8859-1";
  }

static String[] toStringArray(List<String> list) {
  return list.toArray(new String[list.size()]);
}

static String[] toStringArray(Object o) {
  if (o instanceof String[])
    return (String[]) o;
  else if (o instanceof List)
    return toStringArray((List<String>) o);
  else
    throw fail("Not a list or array: " + structure(o));
}

static File getGlobalCache() {
  File file = new File(userHome(), ".tinybrain/snippet-cache");
  file.mkdirs();
  return file;
}

static String sendToLocalBot(String bot, String text, Object... args) {
  text = format3(text, args);
  
  DialogIO channel = findBot(bot);
  if (channel == null)
    fail(quote(bot) + " not found");
  try {
    channel.readLine();
    print(bot + "> " + shorten(text, 80));
    channel.sendLine(text);
    String s = channel.readLine();
    print(bot + "< " + shorten(s, 80));
    return s;
  } catch (Throwable e) {
    e.printStackTrace();
    return null;
  } finally {
    channel.close();
  }
}

static String sendToLocalBot(int port, String text, Object... args) {
  text = format3(text, args);
  DialogIO channel = talkTo(port);
  try {
    channel.readLine();
    print(port + "> " + shorten(text, 80));
    channel.sendLine(text);
    String s = channel.readLine();
    print(port + "< " + shorten(s, 80));
    return s;
  } catch (Throwable e) {
    e.printStackTrace();
    return null;
  } finally {
    if (channel != null)
      channel.close();
  }
}
// works on lists and strings and null

static int indexOfIgnoreCase(Object a, Object b) {
  if (a == null) return -1;
  if (a instanceof String) {
     Matcher m = Pattern.compile((String) b, Pattern.CASE_INSENSITIVE + Pattern.LITERAL).matcher((String) a);
     if (m.find()) return m.start(); else return -1;
  }
  if (a instanceof List) {
    for (int i = 0; i < ((List) a).size(); i++) {
      Object o = ((List) a).get(i);
      if (o != null && ((String) o).equalsIgnoreCase((String) b))
        return i;
    }
    return -1;
  }
  throw fail("Unknown type: " + a);
}
static boolean startsWithIgnoreCase(String a, String b) {
  return a != null && a.regionMatches(true, 0, b, 0, b.length());
}
static String md5(String text) { try {
 
  if (text == null) return "-";
  return bytesToHex(md5_impl(text.getBytes("UTF-8"))); // maybe different than the way PHP does it...

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}

static String md5(byte[] data) {
  return bytesToHex(md5_impl(data));
}

static byte[] md5_impl(byte[] data) {
 try {
  return MessageDigest.getInstance("MD5").digest(data);
 } catch (Exception e) { throw e instanceof RuntimeException ? (RuntimeException) e : new RuntimeException(e); }
}

static String md5(File file) { try {
 
  return md5(loadBinaryFile(file));

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static String firstPartOfHelloString(String s) {
  int i = s.lastIndexOf('/');
  return i < 0 ? s : rtrim(s.substring(0, i));
}
static boolean isInteger(String s) {
  return s != null && Pattern.matches("\\-?\\d+", s);
}
 static String getSnippetFromBossBot(long snippetID) {
    return boss(format3("get text for *", snippetID));
  }
  
  /** writes safely (to temp file, then rename) */
  public static void saveTextFile(String fileName, String contents) throws IOException {
    File file = new File(fileName);
    File parentFile = file.getParentFile();
    if (parentFile != null)
      parentFile.mkdirs();
    String tempFileName = fileName + "_temp";
    if (contents != null) {
      FileOutputStream fileOutputStream = new FileOutputStream(tempFileName);
      OutputStreamWriter outputStreamWriter = new OutputStreamWriter(fileOutputStream, "UTF-8");
      PrintWriter printWriter = new PrintWriter(outputStreamWriter);
      printWriter.print(contents);
      printWriter.close();
    }
    
    if (file.exists() && !file.delete())
      throw new IOException("Can't delete " + fileName);

    if (contents != null)
      if (!new File(tempFileName).renameTo(file))
        throw new IOException("Can't rename " + tempFileName + " to " + fileName);
  }
  
  public static void saveTextFile(File fileName, String contents) {
    try {
      saveTextFile(fileName.getPath(), contents);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }

  /** writes safely (to temp file, then rename) */
  public static void saveBinaryFile(String fileName, byte[] contents) throws IOException {
    File file = new File(fileName);
    File parentFile = file.getParentFile();
    if (parentFile != null)
      parentFile.mkdirs();
    String tempFileName = fileName + "_temp";
    FileOutputStream fileOutputStream = new FileOutputStream(tempFileName);
    fileOutputStream.write(contents);
    fileOutputStream.close();
    if (file.exists() && !file.delete())
      throw new IOException("Can't delete " + fileName);

    if (!new File(tempFileName).renameTo(file))
      throw new IOException("Can't rename " + tempFileName + " to " + fileName);
  }

  static void saveBinaryFile(File fileName, byte[] contents) {
    try {
      saveBinaryFile(fileName.getPath(), contents);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  public static String loadTextFile(String fileName) {
    try {
      return loadTextFile(fileName, null);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  
  public static String loadTextFile(String fileName, String defaultContents) throws IOException {
    if (!new File(fileName).exists())
      return defaultContents;

    FileInputStream fileInputStream = new FileInputStream(fileName);
    InputStreamReader inputStreamReader = new InputStreamReader(fileInputStream, "UTF-8");
    return loadTextFile(inputStreamReader);
  }
  
  public static String loadTextFile(File fileName) {
    try {
      return loadTextFile(fileName, null);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }

  public static String loadTextFile(File fileName, String defaultContents) throws IOException {
    try {
      return loadTextFile(fileName.getPath(), defaultContents);
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
  
  public static String loadTextFile(Reader reader) throws IOException {
    StringBuilder builder = new StringBuilder();
    try {
      char[] buffer = new char[1024];
      int n;
      while (-1 != (n = reader.read(buffer)))
        builder.append(buffer, 0, n);
        
    } finally {
      reader.close();
    }
    return builder.toString();
  }
static byte[] loadBinaryPage(String url) throws IOException {
  return loadBinaryPage(new URL(url).openConnection());
}

public static byte[] loadBinaryPage(URLConnection con) throws IOException {
  //setHeaders(con);
  ByteArrayOutputStream buf = new ByteArrayOutputStream();
  InputStream inputStream = con.getInputStream();
  int n = 0;
  while (true) {
    int ch = inputStream.read();
    if (ch < 0)
      break;
    buf.write(ch);
    if (++n % 100000 == 0)
      System.err.println("  " + n + " bytes loaded.");
  }
  inputStream.close();
  return buf.toByteArray();
}

static String fromUtf8(byte[] bytes) { try {
 
  return new String(bytes, "UTF-8");

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static void startBotSeparateVM(String botName, String scriptID) {
  DialogIO bot = findBot(botName);
  if (bot != null)
    bot.close();
  else {
    print("Bot " + quote(botName) + " not found. Starting separately: " + scriptID);
    nohupJavax(scriptID);
    waitForBotStartUp(botName);
  }
}

// currently finds only inner classes of class "main"
// returns null on not found
// this is the simple version that is not case-tolerant
static Class findClass(String name) {
  try {
    return Class.forName("main$" + name);
  } catch (ClassNotFoundException e) {
    return null;
  }
}
 static String boss(String line) {
    try {
      //S s = sendToLocalBotOpt("Boss Bot", line);
      DialogIO io = talkTo(4990); // Boss Bot port
      io.readLine();
      io.sendLine(line);
      String s = io.readLine();
      Matches m = new Matches();
      if (match3("text: *", s, m))
        return unquote(m.m[0]);
      return null;
    } catch (Exception e) {
      //e.printStackTrace();
      return null;
    }
  }
static String _userHome;
static String userHome() {
  if (_userHome == null) {
    if (isAndroid())
      _userHome = "/storage/sdcard0/";
    else
      _userHome = System.getProperty("user.home");
    //System.out.println("userHome: " + _userHome);
  }
  return _userHome;
}

static boolean isLongConstant(String s) {
  if (!s.endsWith("L")) return false;
  s = s.substring(0, l(s)-1);
  return isInteger(s);
}
static void nohupJavax(String javaxargs) {
  nohupJavax(javaxargs, "");
}

// vm args are ignored if pre-spun VM found...
static void nohupJavax(String javaxargs, String vmArgs) {
  javaxargs = javaxargs.trim();
  if (javaxargs.startsWith("#")) javaxargs = javaxargs.substring(1);
  String snippetID = javaTok(javaxargs).get(1);
  int idx = javaxargs.indexOf(' ');
  String args = idx < 0 ? "" : javaxargs.substring(idx+1).trim();
  
  String line;
  if (args.length() != 0)
    line = format3("please start program * with arguments *", snippetID, args);
  else
    line = format3("please start program *", snippetID);
  String answer = sendToLocalBotOpt("A pre-spun VM.", line);
  if (match3("ok", answer)) {
    print("OK, used pre-spun VM.");
  } else {
    if (answer != null)
      print("> " + answer);
    print("Using standard nohup.");
    classicNohupJavax(javaxargs, vmArgs);
  }
}
static long parseLong(String s) {
  return Long.parseLong(s);
}
  public static String bytesToHex(byte[] bytes) {
    return bytesToHex(bytes, 0, bytes.length);
  }

  public static String bytesToHex(byte[] bytes, int ofs, int len) {
    StringBuilder stringBuilder = new StringBuilder(len*2);
    for (int i = 0; i < len; i++) {
      String s = "0" + Integer.toHexString(bytes[ofs+i]);
      stringBuilder.append(s.substring(s.length()-2, s.length()));
    }
    return stringBuilder.toString();
  }

static double parseDouble(String s) {
  return Double.parseDouble(s);
}
public static String rtrim(String s) {
  int i = s.length();
  while (i > 0 && " \t\r\n".indexOf(s.charAt(i-1)) >= 0)
    --i;
  return i < s.length() ? s.substring(0, i) : s;
}
public static byte[] loadBinaryFile(String fileName) throws IOException {
  if (!new File(fileName).exists())
    return null;

  FileInputStream in = new FileInputStream(fileName);

  byte buf[] = new byte[1024];
  ByteArrayOutputStream out = new ByteArrayOutputStream();
  int l;
  while (true) {
    l = in.read(buf);
    if (l <= 0) break;
    out.write(buf, 0, l);
  }
  in.close();
  return out.toByteArray();
}

public static byte[] loadBinaryFile(File file) throws IOException {
  return loadBinaryFile(file.getPath());
}


static void classicNohupJavax(String javaxargs) {
  classicNohupJavax(javaxargs, "");
}

static void classicNohupJavax(String javaxargs, String vmArgs) { try {
 
  int x = latestInstalledJavaX();
  File xfile = new File(userHome(), ".javax/x" + Math.max(x, 30) + ".jar");
  if (!xfile.isFile()) {
    String url = "http://tinybrain.de/x30.jar";
    byte[] data = loadBinaryPage(url);
    if (data.length < 1000000)
      fail("Could not load " + url);
    saveBinaryFile(xfile.getPath(), data);
  }
  String jarPath = xfile.getPath();
  if (javaxargs.startsWith("#")) javaxargs = javaxargs.substring(1);
  nohup("java " + vmArgs + " -jar " + (isWindows() ? winQuote(jarPath) : bashQuote(jarPath)) + " " + javaxargs);

} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
static String sendToLocalBotOpt(String bot, String text) {
  if (bot == null) return null;
  DialogIO channel = findBot(bot);
  if (channel == null) {
    print(quote(bot) + " not found, skipping send: " + quote(text));
    return null;
  }
  try {
    channel.readLine();
    print(bot + "> " + text);
    channel.sendLine(text);
    String s = channel.readLine();
    print(bot + "< " + s);
    return s;
  } catch (Throwable e) {
    e.printStackTrace();
    return null;
  } finally {
    channel.close();
  }
}
static boolean isAndroid() { return System.getProperty("java.vendor").toLowerCase().indexOf("android") >= 0; }

public static boolean isWindows() {
  return System.getProperty("os.name").contains("Windows");
}
/** possibly improvable */
public static String bashQuote(String text) {
  if (text == null) return null;
  return "\"" + text
    .replace("\\", "\\\\")
    .replace("\"", "\\\"")
    .replace("\n", "\\n")
    .replace("\r", "\\r") + "\"";
}

/** possibly improvable */
public static String winQuote(String text) {
  if (text == null) return null;
  return "\"" + text
    .replace("\\", "\\\\")
    .replace("\"", "\\\"")
    .replace("\n", "\\n")
    .replace("\r", "\\r") + "\"";
}

static int latestInstalledJavaX() {
  File[] files = new File(userHome(), ".javax").listFiles();
  int v = 0;
  if (files != null) for (File f : files) {
    Matcher m = Pattern.compile("x(\\d\\d\\d?)\\.jar").matcher(f.getName());
    if (m.matches())
      v = Math.max(v, Integer.parseInt(m.group(1)));
  }
  return v;
}
public static File nohup(String cmd) throws IOException {
  File outFile = File.createTempFile("nohup_" + nohup_sanitize(cmd), ".out");
  nohup(cmd, outFile, false);
  return outFile;
}

static String nohup_sanitize(String s) {
  return s.replaceAll("[^a-zA-Z0-9\\-_]", "");
}

/** outFile takes stdout and stderr. */
public static void nohup(String cmd, File outFile, boolean append) throws IOException {
  String command = nohup_makeNohupCommand(cmd, outFile, append);

  File scriptFile = File.createTempFile("_realnohup", isWindows() ? ".bat" : "");
  System.out.println("[Nohup] " + command);
  try {
    //System.out.println("[RealNohup] Script file: " + scriptFile.getPath());
    saveTextFile(scriptFile.getPath(), command);
    String[] command2;
    if (isWindows())
      command2 = new String[] {"cmd", "/c", "start", "/b", scriptFile.getPath() };
    else
      command2 = new String[] {"/bin/bash", scriptFile.getPath() };
      
    Process process = Runtime.getRuntime().exec(command2);
    try {
      process.waitFor();
    } catch (InterruptedException e) {
      throw new RuntimeException(e);
    }
    int value = process.exitValue();
    //System.out.println("exit value: " + value);
  } finally {
    if (!isWindows())
      scriptFile.delete();
  }
}

public static String nohup_makeNohupCommand(String cmd, File outFile, boolean append) {
  mkdirsForFile(outFile);

  String command;
  if (isWindows())
    command = cmd + (append ? " >>" : " >") + winQuote(outFile.getPath()) + " 2>&1";
  else
    command = "nohup " + cmd + (append ? " >>" : " >") + bashQuote(outFile.getPath()) + " 2>&1 &";
  return command;
}


public static void mkdirsForFile(File file) {
  File dir = file.getParentFile();
  if (dir != null) // is null if file is in current dir
    dir.mkdirs();
}


static class EvalTransform {
  int varCount;
  Exception exception;
  boolean recurse = true;
  
  Lisp newVar() {
    return lisp("$e" + (++varCount));
  }
  
  Lisp transformEval(Lisp tree, List<Lisp> out) {
    if (tree.is("[]", 2) && tree.get(0).is("eval", 0) && tree.get(1).is("()", 1)) {
      Lisp exp = tree.get(1).get(0);
      if (recurse)
        exp = transformEval(exp, out);
      Lisp var = newVar();
      out.add(lisp("[]", var, "=").addAll(nlUnroll(exp)));
      return var;
    }
    
    // recurse
    
    Lisp n = new Lisp(tree.head);
    for (Lisp t : tree)
      n.add(transformEval(t, out));
    return n;
  }
  
  Lisp evalTransformRule(Lisp rule) {
    try {
      List<Lisp> ops = snlSplitOps(rule);
      
      // expand unconditional rule
      if (ops == null || ops.isEmpty() || !ops.get(0).is("if *", 1))
        ops = litlist(lisp("then *", rule));
        
      for (int i = 0; i < l(ops); i++) {
        Lisp op = ops.get(i).get(0);
        List<Lisp> out = new ArrayList<Lisp>();
        Lisp op2 = transformEval(op, out);
        if (out.isEmpty()) continue;
        for (Lisp l : out) {
          ops.add(i, lisp(i == 0 ? "if *" : "and *", l));
          ++i;
        }
        ops.set(i, lisp(i == l(ops)-1 ? "then *" : "and *", op2));
      }
      return snlJoinOps(ops);
    } catch (Exception e) {
      exception = e;
      return rule;
    }
  }
  
  Lisp evalTransformQuestion(Lisp question) {
    try {
      List<Lisp> out = new ArrayList<Lisp>();
      Lisp tree = transformEval(question, out);
      for (int i = l(out)-1; i >= 0; i--)
        tree = lisp("[]", out.get(i), "and", tree);
      return tree;
    } catch (Exception e) {
      exception = e;
      return question;
    }
  }
}

static class ProgramScan {
  static int threads = isWindows() ? 500 : 10;
  static int timeout = 5000; // hmm...
  static String ip = "127.0.0.1";
  static int quickScanFrom = 10000, quickScanTo = 10999;
  static int maxNumberOfBotPorts = 100;
  static boolean verbose;
  
  static class Program {
    int port;
    String helloString;
    
    Program(int port, String helloString) {
  this.helloString = helloString;
  this.port = port;}
  }
  
  static List<Program> scan() { try {
 
    return scan(1, 65535);
  
} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
  
  static List<Program> scan(int fromPort, int toPort) {
    return scan(fromPort, toPort, new int[0]);
  }
  
  static List<Program> scan(int fromPort, int toPort, int[] preferredPorts) { try {
 
    Set<Integer> preferredPortsSet = new HashSet<Integer>(asList(preferredPorts));
    String name = toPort < 10000 ? "bot" : "program";
    final ExecutorService es = Executors.newFixedThreadPool(threads);
    if (verbose) print(firstToUpper(name) + "-scanning " + ip + " with timeout " + timeout + " ms in " + threads + " threads.");
    startTiming();
    List<Future<Program>> futures = new ArrayList<Future<Program>>();
    for (int port : preferredPorts)
      futures.add(checkPort(es, ip, port, timeout));
    for (int port = fromPort; port <= toPort; port++)
      if (!preferredPortsSet.contains(port))
        futures.add(checkPort(es, ip, port, timeout));
    es.shutdown();
    List<Program> programs = new ArrayList<Program>();
    for (final Future<Program> f : futures) {
      Program p = f.get();
      if (p != null)
        programs.add(p);
    }
    stopTiming();
    if (verbose) print("Found " + programs.size() + " " + name + "(s) on " + ip);
    return programs;
  
} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}

  static Future<Program> checkPort(final ExecutorService es, final String ip, final int port, final int timeout) {
    return es.submit(new Callable<Program>() {
        @Override public Program call() {
          try {
            Socket socket = new Socket();
            socket.setSoTimeout(timeout);
            socket.connect(new InetSocketAddress(ip, port), timeout);
            if (verbose) print("Connected to " + ip + ":" + port);
            BufferedReader in = new BufferedReader(
              new InputStreamReader(socket.getInputStream(), "UTF-8"));
            String hello = or(in.readLine(), "?");
            socket.close();
            return new Program(port, hello);
          } catch (Exception ex) {
            return null;
          }
        }
     });
  }
  
  static List<Program> quickScan() {
    return scan(quickScanFrom, quickScanTo);
  }
  
  static List<Program> quickBotScan() {
    return quickBotScan(new int[0]);
  }
  
  static List<Program> quickBotScan(int[] preferredPorts) {
    return scan(4990, 5000+maxNumberOfBotPorts-1, preferredPorts);
  }
}

// parser explainer
static class Explain {
  static List<String> primitiveClasses = litlist("quoted", "identifier", "any", "int");
  
  Object parseResult;
  List<String> tok;
  List e;
  List<Explain> subs = new ArrayList<Explain>();
  
  static boolean debug;
  
  Explain(Object parseResult, List e) {
  this.e = e;
  this.parseResult = parseResult;
    tok = (List) get(parseResult, "tok");
    makeSubExplains();
  }
  
  void makeSubExplains() {
    for (int i = 4; i < l(e); i++) {
      List sub = (List) ( get(e, i));
      int t1 = (int) get(sub, 0);
      int t2 = (int) get(sub, 1);
      String className = getString(sub, 2);
      List subE = sub;
      if (!primitiveClasses.contains(className))
        subE = (List) call(parseResult, "explainFull", t1, t2, className);
      if (debug)
        printF("Explaining * * * => *", t1, t2, className, subE);
      if (subE == null)
        subs.add(null);
      else
        subs.add(new Explain(parseResult, subE));
    }
  }
  
  String className() {
    return getString(e, 2);
  }
  
  int fromToken() {
    return (int) get(e, 0);
  }
  
  int toToken() {
    return (int) get(e, 1);
  }
  
  // return tokens, padded with empty non-code tokens first and last
  // to make actual CNC
  List<String> tok() {
    return concatLists(
      litlist(""),
      subList(tok, fromToken(), toToken()-1),
      litlist(""));
  }
  
  String string() {
    return join(subList(tok, fromToken(), toToken()-1));
  }
  
  boolean containsToken(String t) {
    return main.containsToken(tok(), t);
  }
  
  void findAll(String className, List<String> out) {
    if (eq(className, className()))
      out.add(string());
    else // << this is new - don't recurse
      for (Explain e : subs)
        if (e != null)
          e.findAll(className, out);
  }
  
  List<String> findAll(String className) {
    List<String> l = new ArrayList<String>();
    findAll(className, l);
    return l;
  }
  
  // short for findFirst
  Explain find(String className) {
    return findFirst(className);
  }
  
  Explain findFirst(String className) {
    if (eq(className, className()))
      return this;
    return findFirstSub(className);
  }
  
  // find class, but exclude myself
  Explain findFirstSub(String className) {
    for (Explain e : subs)
      if (e != null) {
        Explain result = e.findFirst(className);
        if (result != null) return result;
      }
    return null;
  }
  
  boolean has(String className) {
    return findFirst(className) != null;
  }
  
  boolean hasSub(String className) {
    return findFirstSub(className) != null;
  }
  
  void findAll2(String className, List<Explain> out) {
    if (eq(className, className()))
      out.add(this);
    for (Explain e : subs)
      if (e != null)
        e.findAll2(className, out);
  }
  
  List<Explain> findAll2(String className) {
    List<Explain> l = new ArrayList<Explain>();
    findAll2(className, l);
    return l;
  }
  
  // short for pruneSubs
  Explain prune(String className) {
    return pruneSubs(className);
  }
  
  // returns self after pruning
  Explain pruneSubs(String className) {
    for (int i = 0; i < l(subs); ) {
      Explain e = sub(i);
      if (e == null) ++i;
      else if (eq(e.className(), className))
        subs.remove(i);
      else {
        e.pruneSubs(className);
        ++i;
      }
    }
    return this;
  }
  
  Explain sub(int i) {
    return get(subs, i);
  }
}

// returns null if className is not a parsed main class
static Explain explainParse(Object parseResult, String className) {
  List exp = (List) ( call(parseResult, "explainFull", className));
  if (exp == null) return null;
  return new Explain(parseResult, exp);
}

static String findBestMatch(String query, List<String> cmds) {
  query = query.toLowerCase();
  Map<String, Integer> map = new TreeMap<String, Integer>();
  for (String cmd : cmds)
    map.put(cmd, l(commonPrefix(cmd.toLowerCase(), query)));
  return highest(map);
}

  static abstract class DialogIO {
    String line;
    boolean eos;
    
    abstract String readLineImpl();
    abstract boolean isStillConnected();
    abstract void sendLine(String line);
    abstract boolean isLocalConnection();
    abstract Socket getSocket();
    abstract void close();
    
    int getPort() { return getSocket().getPort(); }
    
    boolean helloRead;
    
    String readLineNoBlock() {
      String l = line;
      line = null;
      return l;
    }
    
    boolean waitForLine() { try {
 
      if (line != null) return true;
      //print("Readline");
      line = readLineImpl();
      //print("Readline done: " + line);
      if (line == null) eos = true;
      return line != null;
    
} catch (Throwable __e) { throw __e instanceof RuntimeException ? (RuntimeException) __e : new RuntimeException(__e); }}
    
    String readLine() {
      waitForLine();
      helloRead = true;
      return readLineNoBlock();
    }
    
    String ask(String s, Object... args) {
      if (!helloRead) readLine();
      if (args.length != 0) s = format3(s, args);
      sendLine(s);
      return readLine();
    }
    
    String askLoudly(String s, Object... args) {
      if (!helloRead) readLine();
      if (args.length != 0) s = format3(s, args);
      print("> " + s);
      sendLine(s);
      String answer = readLine();
      print("< " + answer);
      return answer;
    }
    
    void pushback(String l) {
      if (line != null)
        fail();
      line = l;
      helloRead = false;
    }
  }
  
  static abstract class DialogHandler {
    abstract void run(DialogIO io);
  }

  static class Matches {
    String[] m;
    String get(int i) { return m[i]; }
    String unq(int i) { return unquote(m[i]); }
    String fsi(int i) { return formatSnippetID(unq(i)); }
    boolean bool(int i) { return "true".equals(unq(i)); }
    String rest() { return m[m.length-1]; } // for matchStart
    int psi(int i) { return Integer.parseInt(unq(i)); }
  }


static String formatSnippetID(String id) {
  return "#" + parseSnippetID(id);
}

static String formatSnippetID(long id) {
  return "#" + id;
}

static <A> List<A> findAll(JFrame f, Class<A> theClass) {
  List<A> l = new ArrayList<A>();
  scanForComponents(f, theClass, l);
  return l;
}
static <A, B extends Number> A highest(Map<A, B> map) {
  return keyWithBiggestValue(map);
}
static long startTiming_startTime;
static void startTiming() {
  startTiming_startTime = now();
}

static void stopTiming() {
  long end = now();
  print("Time: " + (end-startTiming_startTime) + " ms");
}
static boolean containsToken(List<String> tok, String token) {
  return tok.contains(token);
}
static void printF(String s, Object... args) {
  printFormat(s, args);
}
static String string(Object o) {
  return String.valueOf(o);
}
static List<Lisp> nlUnroll(Lisp tree) {
  if (tree.is("[]"))
    return tree.args;
  else
    return litlist(tree);
}
static BufferedReader readLine_reader;

static String readLine() {
  return (String) call(getJavaX(), "readLine");
}
  public static String commonPrefix(String a, String b) {
    int i = 0;
    while (i < a.length() && i < b.length() && a.charAt(i) == b.charAt(i))
      ++i;
    return a.substring(0, i);
  }

static String find(String pattern, String text) {
  Matcher matcher = Pattern.compile(pattern).matcher(text);
  if (matcher.find())
    return matcher.group(1);
  return null;
}
static String firstToUpper(String s) {
  if (s.length() == 0) return s;
  return Character.toUpperCase(s.charAt(0)) + s.substring(1);
}

static <A, B extends Number> A keyWithBiggestValue(Map<A, B> map) {
  A best = null;
  Number bestScore = null;
  for (A key : keys(map)) {
    Number score = map.get(key);
    if (best == null || cmp(score, bestScore) > 0) {
      best = key;
      bestScore = score;
    }
  }
  return best;
}
static void printFormat(String s, Object... args) {
  print(format(s, args));
}
static <A> void scanForComponents(Component c, Class<A> theClass, List<A> l) {
  if (theClass.isInstance(c))
    l.add((A) c);
  if (c instanceof Container)
  for (Component comp : ((Container) c).getComponents())
    scanForComponents(comp, theClass, l);
}

static int cmp(Number a, Number b) {
  return a == null ? b == null ? 0 : -1 : cmp(a.doubleValue(), b.doubleValue());
}

static int cmp(double a, double b) {
  return a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(String a, String b) {
  return a == null ? b == null ? 0 : -1 : a.compareTo(b);
}

static int cmp(Object a, Object b) {
  if (a == null) return b == null ? 0 : -1;
  return ((Comparable) a).compareTo(b);
}
static <A, B> Set<A> keys(Map<A, B> map) {
  return map.keySet();
}

static Set keys(Object map) {
  return keys((Map) map);
}
}